Sounds like you're in the high school phase. I've been through there. Middle to high school was the worst time for me. Once I was out of high school, not a single person impersonated me. As you and people age, it will matter less and people become more aware and respectful to others. It gets better and people become more understanding. Just hang in there. Best thing I can tell you is to either stand up for yourself and confront them or ignore them. Now if these were your "friends", I suggest getting new friends; but this doesn't seem to be the case.