I'm really just confused and frustrated

I'm really just confused and frustrated I'm 16m, by the way. I've always stuttered, but until about the seventh or eight grade, I didn't really let it bother me much. I'm a junior now, in my third different high school after my family moved halfway across the country again, and my stutter has only gotten stronger as it makes me feel weaker. I know people say stuff like 'talk to family and close friends', and 'just stay strong and you'll get through it', but when I'm always the new kid, it seems like they're just trying to sell lies. After being bullied and made fun of in the past, I always feel skeptical about anyone who even tried to talk to me. I don't know if it's because I stutter or because I'm a teenager, but I just feel stressed out and depressed all the time. Now that I think about it, I haven't been able to sleep well in a long time, but no matter what, it seems like my own mind is my worst enemy.