Today my LDR girlfriend is going to a concert with one of her friends and I can't help but feel so many stupid emotions about it. I feel like she's going to cheat on me even though I know she's not, and I feel like her friend is going to make her break up with me because of my behavior. Lately I've been getting more and more agitated with her because of jealousy (?? I don't even know if jealousy is the right word, I just get sad when she does things without me.) ... 

The dumbest part is, I'm simultaneously constantly clingy and need to be calling with her 24/7, AND I can't stand talking to her because I'm so upset at her for doing things without me. I know all of this is 100% irrational but it's so hard to break free from this cycle... Does anyone have advice??? I would really really appreciate it :(((