Usually it is my dog, specifically, then the rest of my pets I chose to adopt. But if I'm in a reallly reallly bad place, what motivates me is that even though I fantasize about dying, I'm too lazy to achieve the goal. And, even if I tried to end my life I probably wouldn't do it right, then I'd become a vegetable, or worse, conscious again...which would be a whole nother bag of fun.

And also what Shattered Sanity said.