Questions: Break Up & Divorce

i found out that my ex boyfriend is dating my roommate. well here's some background. ex and I first started dating in 8th grade going on and off. we split up before college because he didn't want to have a long distance relationship and I really hurt. well this is year 4 for me and him in college and earlier this week I saw him on campus. I said hi and we talked for a little bit and I found out that he had transfered. Well anyway back to the problem. yesturday I walked in on my roommate and him while they were shoving their tongues down each others' throat. I was shocked and I dropped every thing and ran out cause I just totally FREAKED. Well later last night when I finally thought I had calmed down, I went back to my room, slowly opened the door and walked in. they were both sitting there on the couch looking down at their hands. My roommate ask if I was okay, and I was like hell no. then she started crying and so did i. my ex just sat there like thinking I guess and he then finally said, I didn't know you two knew each other. and... I jumped in and said, why? why did you say that you didn't want a long distance relationship and yet you have one? he answers I didn't want to hurt you and I didn't know what to do or say. I mean I loved you both so much and I couldn't choose. my roommate goes, "and yet you still chose me and you dip her off?"

i ran out of the room after that and spent a night with my guy friends in their place. Today I just don't feel like trying to talk to either one of them.

Am I being to freaked or should I just go on? PLEASE HELP ME!