[MIABroken]

This is my first post on here. I broke up with my gf a few months ago. We dated for about 8 months. I have had a few gf's in the past that when we broke up it was sad but something that I could get over. Most of my relationships were long term. (over a year) but somehow in just 8 months I fell harder for this one than any of them. I have had the worst luck with girlfriends almost everyone has cheated on me and gone on to either have a relationship with the person or merry the person. This girl did not cheat on me but she started having feelings for a co worker in the company we work for. We were already broken up so I didn't mind who she dated and still don't. I think it was wrong that it is right in front of me and I have to see it everyday.(She started dating him a few weeks after we broke up) My ex always said she cares and we were getting along better then ever after we broke up and she knew full well the troubles that I have had with past girlfriends. I know she didn't cheat but it really feels like it. I trusted her and seeing it right in front of me feels like she never cared and just constantly stabbed me with a dagger. If I was in a relationship with someone and I knew they still had feelings for me I would never date another person in front of them let alone in the same company in the same office.
This has totally screwed me up. It might be because its the final wound in a long line of them. Or the fact that I loved her more than I thought I could love anything in the world.
Now I see them together and its like she never cared about me at all. Basically I look at it like a selfish act on her part and I told her how I felt about it and that I didn't think it was right at all. She took it very personally and now not only do I have to put up with this in front of me she refuses to talk to me and is very defensive and just puts up with me. (I think she might be hypersensitive)
I am also just really confused about the whole time we dated. She said toward the end that she viewed our relationship as just casual, but we went out and hung out a lot for 8 months. Casual relationships don't last that long, do they? We were exclusive with each other and we talked all the time and hung out about 4 days a week. I think its kind of insulting to our relationship to just call it casual.
I never really figured out the downward spiral of our relationship and I think that's what drives me crazy. She said she never really liked me like that, but we slept together and dated for 8 months, that's a while right? Between her being capable of being mean and dating one of my friends/co-worker, and her telling me that we were really nothing. It really hurts unlike any post relationship I have been through.
I think I might be depressed over it. Its constantly on my mind from when I wake up to when I go to sleep. Even in my dreams, I have had the worst sleeps ever. I have this feeling in the pit of my stomach all the time and I constantly cry over the littlest things now. I don't want to do any work. It really is driving me crazy and is literally the only thing I think about, its driving me nuts. Thanks for listening to me.

Hello, MIABroken. You are grieving. You have not accepted the breakup and harbor a lot of anger. This is your issue to deal with. I do not believe your ex-friend is doing anything wrong.

Good luck in getting through this.