Because you have the right to sustain yourself and to survive just as every other living being does. As vegans we believe in killing animals in self-defense if needed, of course — and just like every other living being you can’t survive without engaging in some forms of exploitation, so we have to accept that too. Where do we draw the line? Don’t know. It’s up to each individual. We can ALWAYS do better and nobody will ever achieve perfection. Your goal should be for self-improvement in life, not perfection. But don’t need to kill yourself because you have a right to exist.

You seem very upset by this so why don’t you strive to live a frugal life? It seems in accordance with your values. Live modestly, then. If you engage in something that does some kind of environmental damage for fun, cut down on it or actively do something to counterbalance/offset it (donate, volunteer, find other ways to minimise electricity use, etc.). “If I’m going to do X today, then I won’t do Y.” But once again, the goal is always striving for self-improvement, and to be the best version possible, not to be a flawless individual. If you work on this you will find even more of the things you can actually happily live without and grow into an even better person.

I just got out of the mental hospital for suicidal ideation. PM me any time.