The lyrics to Billie Eilish's song "when the party's over" appear to be about a toxic relationship that the singer knows should end, but they struggle with the idea of being alone. The opening line, "Don't you know I'm no good for you?" suggests that the singer is aware that they are not good for their partner, but they continue to be with them anyway. The line, "I've learned to lose you, can't afford to" could suggest that the singer has lost their partner before, but they can't afford to lose them again.

The line "Tore my shirt to stop you bleedin', But nothin' ever stops you leavin'" could be interpreted in a few ways. It could suggest that the singer is willing to sacrifice themselves to stop their partner from leaving, but no amount of sacrifice is enough to keep them in the relationship. Alternatively, it could mean that the singer has tried everything to fix the relationship, but nothing seems to work.

The chorus, "Quiet when I'm comin' home and I'm on my own, I could lie, say I like it like that, like it like that" suggests that the singer is uncomfortable with their own company and lies to themselves to cope with the loneliness. They try to convince themselves that they enjoy being alone, but in reality, they crave companionship.

The line, "Don't you know too much already? I'll only hurt you if you let me" suggests that the singer recognizes that they have the potential to hurt their partner and warns them against getting too close. The line "Call me friend but keep me closer" could mean that the singer wants to maintain the relationship, but on their terms.

The bridge, "But nothin' is better sometimes, Once we've both said our goodbyes, Let's just let it go, Let me let you go" suggests that the singer knows that ending the relationship is for the best and they should just let it go. However, they still struggle with the idea of being alone and letting go of the toxic relationship.

Overall, the song appears to be about a toxic relationship that the singer knows should end, but they struggle with the idea of being alone. They recognize that they are not good for their partner but still want to maintain the relationship on their terms.