I should I get over the fact that he's way too nice to every girls?

I get the jelousy part and where it's coming from but babe just ask him about their relationship and tell him it bothers you when she calls him "lovey"! lol. I honestly think if they are that close and they wanted to be together they probably would have been! he obviously see something in you that he didn't see in her, that's why he's with you. Just mention it and move on. hopefully he'll do something about it but try to focus more on what you guys have together and not what they have.