I couldn't imagine making it *that* many more years with the constant fiery anguish inside my head (it ebbed and flowed but was everpresent). I felt oddly calm about the thought, like I had just... accepted it. "oh, well I mean yeah, I'm probably not making it to 30, whatever."
I think in some way, taking an idea like that and treating it as fact was some sort of bizarre, twisted self-harm. internalizing & repeating it, making myself believe it, in order to punish myself. "you're worthless", "nobody loves you", "you're going to kill yourself by 30".