Her new memoir is bracingly, sometimes painfully honest, but there is one passage that Cori Bush seriously considered striking out before publication.

She had an abortion when she was 19. Walking into the white-walled room of a reproductive health clinic, Bush writes, she began to have reservations about the procedure. Twice she told a nurse, “I don’t want to do this,” but twice the nurse ignored her objections and carried on.

Bush heard “the awful sounds as the vacuum sucked the fetus out of my body … I remember the intense pain and the feeling of helplessness in that moment. I was furious. That doctor ignored my pleas. I was just another person in his assembly line, just another little Black girl.”

As the prologue observes, The Forerunner is not your typical political memoir. Bush, 46, is not your typical politician. She is a registered nurse, ordained pastor, community activist and organiser and single mother. A Democrat from St Louis, she is the first Black woman to represent Missouri in the US Congress. She is also a survivor and embodiment of resilience.

She realises that her frank recollection of abortion as a traumatic experience is politically loaded and could be seized upon by anti-abortion activists to further their cause. It comes just a month before midterm elections in which Democrats hope to tap into public anger over the supreme court’s decision to torch the constitutional right to abortion.

“I know that many supporters of reproductive rights will be outraged by my decision to share this story,” the congresswoman writes.

Yet in a phone interview, she tells the Guardian she has no regrets about including it. “It was a difficult position but this memoir is me telling my story,” she says. “To silence me, to tell me you shouldn’t tell this story because someone else can use it and weaponise it, that’s not an answer. We’ve got to fix the problem. The way to make sure that the problem is highlighted and awareness is placed on the issue is to talk about it.”

While the abortion debate is often oversimplified, Bush is offering a reminder of the messy, nuanced reality that she faced as a young Black woman restrained by white medical providers. She continues: “Speaking about what happened wasn’t to condemn abortion providers at all because I work closely with a bunch of providers and reproductive health clinics and I support them.

“It’s something that should not have happened to me and it is our work to not only fix certain parts of the system of harm; it is to do the work to fix all of it. But as I also wrote in my book, I was still able to have the services that I needed and the decision was mine to make. In the end, I made the right decision for me.”

On the day in June that the supreme court’s rightwing majority overturned its 1973 Roe v Wade ruling, Bush happened to be back at the same clinic where she had undergone that difficult abortion (along with a previous abortion that resulted from a rape when she was 17). The congresswoman was meeting with providers, advocates and the health secretary, Xavier Becerra, when the news came through.

“My chief of staff walked up to me during the conversation and showed me his phone and I couldn’t believe it at first. I kept blinking and looking at his phone. Even though we knew that it was most likely going to come any day, it was still hard to see and for that reality to set in.

“Someone said it out loud and stopped the conversation: ‘The supreme court just overturned Roe.’ We all embraced one another. I shed tears, I yelled, I hollered out because I was thinking about the millions of people across this country that will be affected by this.”

The court’s decision led to a surge of women registering to vote in some states. In Missouri’s neighbour Kansas, people voted overwhelmingly to continue to protect abortion in the state constitution. But recent midterm opinion polls suggest that Democratic anger over Roe v Wade could be eclipsed by Republican concerns over inflation and crime.

Bush insists, however: “It’s a huge motivator because we have to remember that this is something that had been in place since 1973 – this was in place when I was born. There are a lot of us that only know a Roe v Wade society and there are people who may not agree with abortion but they also don’t agree with their rights being stripped away. Those folks are saying that’s going to make me show up to vote for the Democrat because I don’t want my rights being taken away.”

Bush brings lived experience to Capitol Hill in ways unthinkable for a career politician. Having been evicted from her home several times, forcing her to sleep in her car with her children, last year she slept on the steps of the US Capitol in protest after Congress failed to pass legislation to extend an eviction moratorium (the White House eventually issued a new eviction moratorium).

In 2014 she was on the frontlines of the uprising in Ferguson, Missouri, after the police killing of unarmed Black teenager Michael Brown. This made her a target for harassment. Her tyres were slashed while her car was parked in front of the complex where she lived. She came home and found her front door had been tampered with.

Bush needed to move home. In 2016, a few weeks after losing a Democratic primary election for the Senate, she saw a social media post by a local faith healer advertising a house to rent. When she got in touch and went to see it, the man raped her. She describes the assault in unflinching, unforgiving detail and writes: “I whimpered through the pain. It seemed like forever. I felt like dying. I wanted to die.”

Bush explains by phone why she choose to open her memoir with this candid account: “That changed everything and I am still in therapy now. I’m still walking out that journey to healing. It affected my life the way that it did because, when I thought about the sexual assaults I had back when I was 18, early adult, I went for the next 20 years blaming myself, like it was because my shorts were really short or my shirt was low or where I was when I met the person. I carried that for all of those years.

“This time I had just completed my first run for office and lost; I was grieving that but I was a registered nurse now, I was taking care of two kids, I had just come from work, I was in my scrubs uniform, I was going to a place to see a home. That’s what really rocked me. Before, I thought it was because of something I did; I didn’t do any of those things this time; I wasn’t drinking, any of it.

“So that’s why the book had to start with that, because my life turned upside down but, as I’m working through it, I’ve been able to help so many others and so many others have also helped me to be able to move forward.”

After the rape, Bush was horrified by the lack of discretion she was afforded. She tells how “a caravan” of people followed her to hospital and she was subjected to the humiliation of a rape kit. A forensic exam found that the encounter could have been an assault or, as the rapist had claimed, consensual rough sex. Bush went to court four times to get a protection order against the faith healer but repeatedly lost.

As a Christian, has she been able to forgive the man who raped her? She pauses. “Let me just say I have some forgiveness but is there a blanket all-is-forgiven? I’m still working through that. I’ve always believed that forgiveness is for you, not for the other person, and so usually I’m quick to forgive.

“But in this instance, because there was some trust there and he hurt me the way that he hurt me and then he lied as a man of God and preacher of the gospel, and he continues on in this lie and continues to evade the system, that has made it difficult for me to just be like, yes, I forgive him and I’m going on with my life.”

The Forerunner also gives Bush’s insider account of joining thousands of activists on the streets in response to the 2014 shooting of Brown in Ferguson. She recalls how the skin on her face and arms burned after police fired teargas. The uprising went on for more than 400 days and, Bush argues, became a pivot point in the centuries-long struggle for Black liberation.

It also foreshadowed the nationwide protests for racial justice that followed the police murder of George Floyd in Minneapolis in 2020. But calls from Bush and others to “defund the police” met with a predictable backlash, even from Joe Biden and other Democratic leaders. Some fear that the momentum of Black Lives Matter is again being lost.

But Bush contends that the working and the organising goes on: “Even if we’re not on the streets every single day chanting and marching, are we organising folks to get them to the polls? Are we organising groups to be able to teach people what to do if you get pulled over by the police? Are we organising groups to teach white people how to talk about and understand racism? Are we mobilising people to support our immigrant community if they’re under attack? Are we organising for repro rights?”

She accuses Republicans of wilfully distorting the central idea of defund the police, which means reallocating funding away from police departments to mental health workers, social workers and other government agencies. “They would rather scare their people instead of educating them.”

Bush became a leader of the movement seeking police and criminal justice reform in Ferguson and across the St Louis area. She lost a Democratic primary race for a congressional seat in 2018 but, with the backing of progressive group Justice Democrats, prevailed in 2020 over a 20-year incumbent. She was instantly embraced as a member of “the squad” in the House of Representatives; Alexandria Ocasio-Cortez describes her as a “sister-in-service”.

There have been wins and losses under Biden, a longtime moderate. The president declared racial equity a central plank of his agenda, appointed a diverse cabinet and far outpaced his predecessors in nominating women and people of colour to the federal bench. But legislation on police reform and voting rights stalled in a Congress where Democrats command only narrow majorities. Bush regards the glass as half full.

“Joe Biden has absolutely surprised me,” she says, citing his decisions to commute the sentences of 75 people serving time for nonviolent drug offences, cancel billions of dollars in student loan debt and lift a pandemic-related expulsion policy that effectively closed America’s asylum system at its border with Mexico.

Many idealists have arrived in Washington only to find their dreams crushed by compromise. Is Bush changing Congress or is Congress changing her? She laughs. “Congress is changing me a little bit in the way of helping me to see how, by pushing, our government can work for the regular everyday person. Not understanding the inner workings of Congress before, I wasn’t able to see it but I knew that I needed to go inside of it to push for the change I wanted to see.

“But mostly I’m changing Congress because I’ve been there less than two years and we have been able to bring about some change and, if nothing else, my colleagues know where I stand on issues. They don’t have to wonder what’s going to happen if a policing bill comes forward, if we talk about Israel-Palestine, if they relate to equity and inclusion, anything that has to do with incarceration rates. There is no question. People know that I stand on the side of equity and equality.”