Have had tom many heartaches..got a good guy..scared of him leaving..What to do?

Oaky...so i met this really great guy in june and we started datein on July 4th and before that i just got out of really sucky realtionship like 3 months ago..and in the past i have been hurt alot and so i just keep freaking myself out like if this guy is goin to leave me or what.His name is chase and he is super great guy and he is nice and careing and supports me and he's super cute..and he's just different from any other guy i have dated.I guess im scared of losing him and to make things even more complicated i maybe fallin for him..and i don't know if i want to..i watch myself of what is say so i don't scare him off and i don't know.How do i get rid of this anxiety of thinking he's goin to leave me ..or how can i just accept the fact that i acctual deserve a great guy? i keep doing the "what ifs" like What if this guys leaves or this is too good to be true when is this all goin to be done..HELP!!