Hi OP, your bf sounds kinda like me, so heres my input:
1) He is jealous of the other guys possibly because he is insecure!
2) You shouldn't break up with him because I think his jealousy is also his immature way of showing that he cares a lot for you.
3) Adorable faces are cool. (n_n)
Conclusion: Don't break up with him!
(By the way, you should try to make him less insecure if that is the problem)
P.S. Is he a Scorpio? ~_~