Plimpton, 51, a co-founder of A is For — an organization dedicated to ending the stigma against abortion care — tells PEOPLE that the Supreme Court's decision earlier this year to overturn Roe v. Wade "hits close to home."
She says, "I know how many people are going to suffer and are suffering."
The Emmy Award-winning Good Wife actress has previously been open about having an abortion long before the landscape of women's reproductive rights was changed by SCOTUS this summer.
Without having an abortion herself, "I'm sure it would've changed the trajectory of my whole life," she says. "But what's important is that it didn't. … I had an abortion so that I could have a career and a life that I wanted, so that I could pursue my life."
Plimpton will co-host the upcoming Broadway Acts for Abortion benefit concert event, a fundraiser dedicated to abortion rights, this Sunday in New York City. Patti LuPone, Lea DeLaria, Javier Muñoz, RuPaul's Drag Race star Peppermint and more are slated to perform during the evening's live-band karaoke; Oscar winner DeBose, 31 — who previously performed at Plimpton's annual event — is on the A is For board.
Dianna Bush Photography
Never miss a story — sign up for PEOPLE's free daily newsletter to stay up to date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.
"It did and does still feel like [what] I said on The Tonight Show with Jimmy [Fallon]: I do feel a little bit like I'm at war with my country or my country is at war with me, in a way," DeBose tells PEOPLE, adding that "choice is such a huge topic in our country."
She says, "Everybody wants the choice to be able to own guns, right? So what is the difference between owning a gun and being able to make a choice for your body? You want to be able to choose whether or not you got a vaccine? I understand that. I want the ability to choose whether or not my body births a child."
Plimpton emphasizes that restricting or banning abortions not only affects women, but everybody. "It's a people's issue. It's a humanity issue," she says, noting that transgender and non-binary people are also directly impacted as well as countless others.
RELATED VIDEO: President Joe Biden Signs Second Executive Order Protecting Access to Abortion
The former Goonies star says that she will keep fighting for reproductive justice. "As my friends at Shout Your Abortion and [its co-founder] Amelia Bonow say, 'I'm going to keep aiding and abetting abortion till the day I die. You can't stop me.' You can't stop any of us because it's gonna happen, whether you like it or not," Plimpton says.
West Side Story's DeBose thinks it's important to "hear people talking about abortion," adding: "These situations make us human. They don't make us any less."
"The first thing anybody can do is use the word abortion," Plimpton adds. "It's about not being ashamed."
However, she hopes that abortion care can continue on being safe. "It's so important to us that we not think of this as a time of mourning, but as a time of action," she says. "They have not beat us."
A Is For's annual benefit will be held Oct. 2 at 54 Below in New York City. For more information, click here.