Am I being pathetic?

So far I have been in relationship for more than 3years and that make me to scare of losing it. I am scare that he might get bored of me seeing same face every single day, having sex with the same person over and over and going out with me every time. I tried to put myself into his position and give him some space but I just couldn't. I'm too jealous of every girls he is dealing with, not including his classmates. The young girls might take over my place at any time and he himself told me once that he likes girls with nice boobies and ass which it totally not me.
I feel insecure, tired of stalking his all spacious online activities still he can't help himself being flirty. He told me I'm greedy and super possessive. When it comes to love, you need to be proactive in order to protect it. That's the only way I know and I have no idea how to love a person in proper way. I can't leave him alone where there're many cute girls around him plus he being such a teaser, that would create new episode which I would be played as a villain. Damn he is an ass! I doubt that is he really mean when he said those flirty words. He should behave himself as everyone knows me as his gf and they might think that I can't handle the horny bf. That is simply embarrassing! I suppose to be studying for Final exam by now but I can't just sleep. Sigh** I have to go back to study in order to pass with C, may be C+? I will upload more later. Keep in touch with me guys. (nobody read my blog anyway, I sound like real idiot now) haha..okay Bye!