Most people know me as a quiet, awkward, shy guy. When I try to actually be assertive, stick up for myself, etc. Some people seem to hate me because of it, as in they're used to taking advantage of me, and now when I'm sticking up for myself, instead of them respecting it, they HATE me, get angry at me.

What is the deal with this, what do I do? Is this some problem on my part?

I don't even know if this is the right place to ask.