Broke up with boyfriend

He was a schizo & sociopath we've dated for 10 months. I know he smokes weed but I recently found out he does pills & lsd & maybe more. I had to end it Bc he just isn't for me. I do want to text him but I know I shouldn't I need to just forget & move on. I'm a straight a student , learning how to drive, getting a job. Never had sex or drugs or drank. My mom told me to stay away from people like that & I can't be around that I don't want to be around that. I can't help the urge to text him I know I shouldn't.