Feel super disrespected.

My boyfriend is absolutely in love with me, and I know this. He's been in love with me since seventh grade and we're juniors now, so I'm not, like, //worried// about him cheating but I still get twitchy over certain things and I would like to know if yall think this is valid because I feel crazy. My baby has the chick friend named Emily, and they've been friends for years. They're really close, and talk about everything from family problems to sex lives. My baby and I have been together for six months and he's been friends with Em for years so I never had a huge problem with it, and it helped that she was in a long term relationship. However, for roughly the year before we started dating all my boyfriend's friends would talk about was how badly he wanted to fuck Em. I don't know if that's true or not, as his friends are super sex centered and kind of gross. Anyway, recently Em's relationship ended and she's been clinging to my man because he's sort of her only real friend. I tried to accept it because she needed someone there for here, but I thought and told him she was very flirty w him and put up really relationshipy pictures of him on snapchat and I was a little jealous. He dismissed it. Well, whoop de fucking doo, a few days ago she tells him she has strong feelings for him. I told him I was uncomfortable with him hanging out with her as much as he did, especially because of this. The next night, as soon as he got off work, he went out to eat with her and just her and wasn't going to tell me because he thought I'd get mad. I found out from her snapchat story. This is long as fuck and feels petty as fuck and nobody will probably answer, but I am stupid for getting upset? Would you tell a dude in a relationship you had feelings for him? What should I do?