Working with my girlfriend's ex.
My girlfriend and I have been together for almost 4 years. We have what I believe to be a really good relationship. The one exception to this is that throughout much of our relationship, she has repeatedly brought up ex-boyfriends (talking about them through the course of a conversation).
I usually just ignore this, figuring that it wasn't worth bringing up, not to mention I really didn't feel threatened by this since she wasn't really talking about them in a favorable way. Both of us work for the same company, but in different areas of the company (i.e. we do not actually work together).
A few months ago, her sister mentioned to her that a "friend" from high school was going to be working with us. The way this was brought up was somewhat uneasy, so I asked my girlfriend why this was the case. She told me that she used to be friends with this guy, but that when he got married, his wife didn't like her very much, so the friendship ended.
Eventually, I came to find out that this guy was going to be actually working directly in my department (i.e. I would be regularly working with him on a daily basis). Since it seemed like he was friends with my girlfriend, and she mentioned that he was a nice guy, I felt there was no reason to not be friendly to him just because his wife may not get along with my girlfriend. I began talking to him, and even found out that he knows one of my brothers. I was mentioned to my girlfriend that this guy seemed nice and even knew my brother. She responded by saying, "That's good, I just really hope there isn't going to be any drama." I was confused by her statement, so I inquired further.
After about aweek of this going on, and her continuing to say the "drama" in question would be because of his wife not liking her, I finally asked if the two of them had a relationship. She finally told me, very manner of fact, that the two of them WERE friends throughout much of high school. She said that he met his future wife and she didn't like her, so the friendship suffered.
One day after this guy and his girlfriend at the time had a fight. He came over to my girlfriends home. The two of them had sex, 2 days later he went back to his girlfriend and they later married. The problem I have now is that my girlfriend more, or less, lied to me for quite a while about their relationship. I feel that the only reason why a woman would do that is because there was something she was trying to hide.
Now I am in a position in which I have to work with this guy every day. I am pretty sure that he knows who I am dating, but we have never talked about it. I don't want to be mean to this guy because he may get pissed and start bad mouthing my girlfriend to the other guys in the office. However, my gut instinct to me absolutely disgusted by the whole thing. Every time I see him I think that he may even think that I don't even know about what happened. I keep thinking that despite my girlfriend's denial, she may have feelings for him.
What's worst , now I have even began to have diminished self confidence. I keep comparing myself to this guy in virtually every way. What should I do? Am I just over reacting?