jealousy takes over

I am such a jealous person. i try not to let it get the best of me but it does. anytime someone talks to my girl or invites her over or anything like that i get uncontollably jealous. lately she's been talking to this guy on mibba and honestly i just wanna punch the kids face in for some reason. it's like i have no control over myself when i get jealous, i say things that hurt her and i do things that other people as well. please tell me their are other people like this. and how do i stop being this way?