It hasnt changed who i am, but it's given more things abit of a kick start.
I've toned down alot, which is weird. But where as, if some one was snotty with me. I'd just walk away before T, now i kick off lol.
So its made me more confrontational and given me a back bone, i notice sexual attraction alot more, uhhh what else. And i'm more laid back. Bout it xD

T changes your personality in more subtle ways.  My experience is that it changed some of my attitudes about sex, and it made me a lot less emotional.  But I'll still drop everything to play with a kitty.