Should I erase him out of my life?

I met this guy a month and a half ago. For two weeks he payed tons of attention to me, texted me every morning during finals week and normal days, texted me goodnight, when I didn't text him back he'd send a message like, "Anyone there?". One night he called to say goodnight and he's spending the night at a friend's house and he slipped a "she" in there and he has clothes at her house...and they've had previous relations if you catch my drift. On our second date or so we did the deed (Yes, I know bad idea! ) and yada yada yada talked and stuff, then I had to leave later and it started to rain so he let me borrow a jacket and said I can give it back to him next time. After that I texted him a couple days later to have a nice day and he said "thanks for knowing im not ignoring you". He's busy in school getting a doctorate. For Valentine's I said happy valentines and be my valentine. Then he texted asking me to be his, I said yes and he never replied. And we haven't spoken since Valentine's. I still have his jacket... but I'm not sure if I should just erase this guy out of my phonebook...I know I should but...yea...suggestions? Advice? I know that I know better.