I think that this is about the loss of a woman's virginity (her insistence that "All we did is kiss/
On my grave, I swear," implying that more happened), possibly against her will ("Very able to hold me down"), & her fear of people finding out/fear of being judged (cue: her paranoia about this random man seeming to know something, so she asks Bruno if he let slip what happened)
I think that this is about the loss of a woman's virginity (her insistence that "All we did is kiss/ On my grave, I swear," implying that more happened), possibly against her will ("Very able to hold me down"), & her fear of people finding out/fear of being judged (cue: her paranoia about this random man seeming to know something, so she asks Bruno if he let slip what happened)