Regarding depression:
I used to experience depression, it was constant, and after a while I didn't
even recognize it as depression. I eventually solved it a couple years ago
when I finally accepted a truth about myself I had really known for years,
but always tried to deny out of fear.
Now, I'm no psychologist, so I don't know what is causing you depression. But
the first thing I would suggest: DROP the activism. All of it. When you're
depressed, activism can seem like the only way to convince yourself that
there is any meaning to life. But it doesn't really help. You don't leave
depression from the mild bursts of euphoria that activism gives you, and the
stress, including the stress of everyone disliking you for it, really can
weigh down on you.
In particular, drop the veganism. I've heard anecdotes of depression caused
by a deficiency of fat in the diet. I don't know how true it is, but it can't
hurt to try. Other than that, focus on your mental health. Find a good
therapist to guide you. Sell your soul if you have to. Use proprietary
software if you have to. Nothing is worth compromising your mental health.
Nothing. I promise you that.