This song was kind of her final write off to Justin Bieber (thus why she's in a confessional), she dated him on again/off again for like 9 years (give or take). They had a very tumultuous/toxic relationship that was only exacerbated by the constant media presence. They eventually broke up in 2018 and he got married pretty quickly after.
Her relationship with Justin Bieber was really messed up!! They stayed together for years with so many rumors about he cheating, but he was always begging her to get back with him and he was doing this through the public, kind of putting pressure on her, so she stayed in this situation for years and then she begged him to stop and he was just fine and moved on with another girl (now his wife) while Selena was into pieces - also because she was going through some health issues. I don't hate Bieber but I strongly dislike him for what he did. Selena is one of the sweetest persons out there.
It's about Justin Bieber they dated for so many years, it was a very unstable relationship, he would cheat on her and treat her miserable. He even admitted he was abusive towards woman in his past
