<human>: When my BF met me (3 years ago) he still liked another girl, his older sister's best friend Emily (now 24). Emily had just moved to Tennessee (we live on the East Coast) and BF and her were emailing a lot. I know that Emily liked him too. I don't know if it was love but I know he wanted to be with her. 

Well, Emily wasn't there, he met me and fell in love with me and last year we officially moved into an apartment together. 

I know it's silly but I've ALWAYS been jealous of Emily and sometimes I think that the only reason my BF and I got together was because she was in Tennessee at the time and he couldn't have her. I've talked to him about this and he denies it and says I'm being silly and that he loves me, but I can't help feeling jealous of her. 

My BF is still friends with Emily and because she'll be in the area next month, he invited her to come visit us for a couple days. Boyfriend is having a big party next month (celebrating something work-related) and he's happy she'll be here for it. 
On the one hand I'm a little peeved because he did that knowing how I feel about her but on the other hand I know I'm probably being silly and I know they're good friends. 

I just get sooo jealous just thinking about her coming and I really don't want to hang out with her, which I'm going to have to do. The girl's never done anything to me and I dislike her for no reason and I feel bad about that but I don't want to spend a bunch of days with her. :/

I guess I need you guys to tell me I'm being stupid and to suck it up?

Can you give me the gist of the text in a nutshell?
<bot>: BF invited the girl he was still into when he met me, to visit. I dislike her for no other reason than my own jealousy and I  don't want to spend time with her but kind of have to.