I just realized someone who I thought was a friend was actually jealous of me. Jealous of my job and the fact I had a great girlfriend. I'm not quite sure on how to deal with people like him to be honest. This is probably one of the more aggressive cases in that I don't think he can stand me. I still have to see him at work everyday. I don't feel like I did anything wrong but he needs to grow up in my opinion.

I would just continue being as nice as possible. Super nice if you have too, even if he's not showing it to you. If your funny joke around in a non-aggressive, non-confrontational way and perhaps he will come around to you. I work with a guy who has a disability and I was told he was this mean guy that never has anything nice to say. Well, I don't know this for sure but I felt like his defensive attitude was probably the result of being harassed about his disability that it eventually became a personality trait for him. So what did I do? I started making fun of myself. I didn't try and put myself at a level above him and in fact knocked myself down. Long story short, to me this guy is one of the nicest people I work with but to many others he's still a prick. Sometimes you have to put yourself out there a little and take a hit for the long run.

In your last sentence you say he needs to grow up, and while I'm not doubting you, you hae already fallen into the trap of "he did this, so I'm going to put up a fight." Maybe he just needs you to talk to him a couple times about nothing in general to gain some trust or see you in a new light. Hell, just ask him how he's doing? Just have some light, short conversations with him and see if he warms up to you.