This is actually a really hard one, because as a 6'4, white guy, I don't have to stick up for myself all that often. I may have to stick up for general ideas I believe in (i.e.: feminism or any left-leaning ideology), but yeah, it's hard to determine where I had to stick up for myself specifically.
Apologies for the non-answer. If I think of something, I might post a revision.