it was so unexpected and at the same time devastating , I was at work and she pulled in her car and beside her was one of my male co-workers who I though was my friend and respected me but apparently not . but yeah they had been hanging out this after noon it turns out and went on a romantic hike that they didn't bother to tell me about , like I'm so upset as I like her so much and been trying to get her for a while now and we almost slept togeher once and we get along so well , but this is just too much to even deal with , I just can't stand the though of her seeing another guy from work and the fact I had to find out by accident just makes me so upset rate now .
what do I even say to her after finding this out in the worst kind of way ?
well this isn't going to well , I logged on msn tonight in appear offline mode and she was online as soon as I signed in she went to offline , it doesn't look like were speaking at the moment , this is going to get pretty damm akward I suspect .
With all due respect, you're not dating her nor are you in an exclusive relationship with her. Certainly I understand your emotion and reactions to this, it's shocking! However, she is single and allowed to date and see who she wants.
In terms of the co-worker, I think his behavior is opportunist, disrespectful and he is untrustworthy. I would not mingle with him on a personal level anymore, keep it professional since you have to collaborate.
I don't think it's your place to say anything. I think that if you want the circumstances to change, then consider spending more time with her so you can determine if a relationship is possible.
If you're not exclusively going out there's nothing you have the right to say. She probably just sees it as enjoying being single until she hits it off the right way with someone. For all you or even your co worker knows she could be dating 2 other guys. So you either fight for her by trying to spend time with her like he did or you give up to keep the piece. If she's into him more than you big the bigger man and don't whine about it, just move on.