One of the most affecting moments on Alex the Astronaut’s debut album tells a story that is not her own. I Like to Dance is a striking first-person account of domestic violence, charting an abusive relationship as it turns from innocent romance to something ugly. Sung in her trademark folk-pop style, accompanied by swelling strings, the climax is quiet but stark: “I just wish he’d stop hitting me.”

“I went to a barbecue with a judge, and he told me about a case that he had,” says the singer-songwriter, Alexandra Lynn, down the line from her Sydney home “He’d spoken to a woman in court who had been beaten up by her partner. She was telling him that he was a great guy and that he would never do any of these things – she just fell down the stairs. And then at one point, she just broke down and said, ‘I just wish he would stop hitting me.’ He said it cut like a knife.

“When he told me that, I got goosebumps and had a tear in my eye. I felt like I’ve told my own story 100 million times, and I have a voice that people listen to, so I should use my skills to help others.”

To write the song, the 25-year-old interviewed domestic violence support workers and immersed herself in true stories of women’s lived experiences. “Trauma is very universal, but you have to get it right,” she says. “People with traumatic experiences need the specifics of what’s happened to them to be told in a fair and truthful way. I did a lot of research to make sure that all those things were as truthful as they could be in a fictional story, so that anyone who heard the song could feel like it was about someone close to them.”

The song represents a shift away from what Lynn is known for; telling stories from her own life. In 2017 she released a single called Not Worth Hiding: a plain and honest message about queer self-acceptance. The song became an unofficial anthem of the yes vote during Australia’s marriage equality referendum, cementing Lynn as a young role model for the LGBTQIA community. Three years on she’s still surprised by the experience: “If I told myself when I was 16 that I would be in this position, I would never have guessed that. I didn’t want to tell anyone that I was gay, let alone millions of random strangers.”

With her debut album, though, the songwriter didn’t want to limit her lyrics to this one aspect of herself. “I’m still young and I don’t think that the world we live in is equal yet,” she says. “It’s still hard for me some days, so sometimes in my songs I don’t really want to talk about that – and, honestly, it doesn’t really come up as much as a writing topic for me anymore. But maybe I’ll come back to that experience and have a different perspective on it at some point.”

The personal and universal collide on The Theory of Absolutely Nothing. The record does not shy away from dark topics – the song Lost chronicles a teenager’s experience with unwanted pregnancy – but it also celebrates the fun parts of life, like falling in love (Christmas in July) and lifting up your friends (I Think You’re Great). Inspired by the conversational storytelling of Paul Kelly, there are minimal bells and whistles here – just a young woman, her guitar and her view of the world. There’s a strong undercurrent of nostalgia, too, as Lynn grapples with the confronting realities of growing up – on Split the Sky, she asks, “If I sit here and watch Harry Potter, will I be all right?”

“Some of the songs feel like photos, or like scrolling back through your social media. It’s a very visceral feeling,” she says. “It’s nice being a songwriter because if you write a song that you connect to it’s almost like a time machine.”

After two EPs released in 2017, writing her first full record was a learning experience: growing up, Lynn admits, she didn’t listen to albums – the first she ever played from start to finish was Frank Ocean’s 2012 debut Channel Orange. “I only started listening in the past three years when I’ve been in the music industry, and I felt like I had to be a big proper musician person,” she says. “Now I’m a massive album fan. I sit and listen to albums [with] the lyric sheet and go through the lyrics, which is just so cool.”

Lynn’s music is the sound of a young person making sense of the world through confession and curiosity. There’s a real sense of hunger to know more about other people: their stories, what makes them tick and what it is that connects us all, no matter how difficult it may be to face. “It’s about painting the light and the dark,” she says. “I think that’s how we experience life.”

• The Theory of Absolutely Nothing is out on Friday 21 August

• If you or someone you know is impacted by sexual assault or family violence, call 1800-RESPECT on 1800 737 732 or visit www.1800RESPECT.org.au