I have had near-constant suicidal thoughts for 21 years. I made two attempts when I was quite young, but not after that. I did, however, engage in a LOT of self-destructive behavior.
I didn't make any further attempts for two reasons -- first, I had genuine hope that my life would get better. It was just a teeny glimmer of hope, but it was there. Second, I had an elderly cat with a chronic illness. I knew that if I died, she would get put down in a shelter. She is the only living creature who ever loved me and she was the only reason I stayed alive. She died in March. I'm still absolutely devastated. I got another cat pretty quickly because I thought it would help, but we don't have the same kind of bond so I guess I'm "at risk."
It has become apparent that my life really is hopeless (please, no one tell me that there's always hope -- that simply isn't true). Basically, I'm just waiting around until I get bored with my current stash of video games.
I do weird things to prevent myself from being impulsive. This will sound weird, but my apartment is filthy and I can't get myself to clean it. I think I'm protecting myself in a way, because I'd never want to be found dead in an apartment this dirty. So, yeah, I'm not doing anything any time soon. I'm 35, though, and I doubt I could live to 40. That said, I said the same thing about being 21 and being 30, and here I am. I wish I'd succeeded at 15. I'd have saved the whole world a lot of disgust and trouble, and I'd have saved myself a lot of trauma and pain.