I hate myself and I think my girlfriend is going to fall in love with another girl.

[Distraughtandbeauty]

For the past many months, I have had a constant fear of my wonderful girlfriend falling in love with someone new, and it gets in the way of many things. If she says she's going out with friends, I get angry and jealous, even though I know it's wrong. But maybe I get so angry and jealous because I myself don't actually have any friends at all.
Recently she said she was going to go to the Harry Potter studios with other people, and it broke my heart, because I had said I wanted to go with her.
I guess what I'm trying to say is that it's getting in the way of everything, and I don't know how to stop obsessing, and it'll only get worse when I move away. I just want to be with her, we have such a good relationship besides the obsessions I have, and she knows they're there, and she understands why I get upset. But I just want them to go away.

[FallonRose]

I'm so sorry that you're feeling this way. Communication is key for any kind of relationship, and you indicated she knows why you act like that but have you actually tried talk with her about it and how to ease any concerns?
You could also try and talk with someone about why you're feeling this way as well? There may be someone who could help you talk this through and maybe help you make sense of your feelings and work through it?