I am having some problems in my relationship and it's absolutely my fault. I have a boyfriend of 5 years and so far we had a great relationship. We were a great team, made of just the two of us.

I had to go on a business team building trip and was displeased to be away for a week from home, but it was obligatory. We talked every day and everything was fine.

When I came back I changed my way of thinking. Mind you, I'm still in my early twenties and I find it healthy that I want to change somethings in my life. I changed my eating habit, got a healthier workout plan and decided to continue my education. For me it's just an opportunity to grow as a person. I feel alive again after so long but my boyfriend has a little problem with all the extra hours at work I've been putting in. He just doesn't approve of my idea of having something that's only mine and not ours. That would maybe not be a big deal, but what is worst is that my feelings towards him have changed, not that I've been showing it. I have just been keeping all the stuff in.

When we were on the trip one colleague of mine,my lower superior and the person with who I needed to cooperate on a job, was getting to talk to me more often. He would be calling me up to check things, asking me this and that, showing me around etc. We got to talk about informal things and when we got back we started working more together. He has been highly supportive of me and I appreciate that very much. I never thought of him as someone that I could grow to like more than on a co-worker basis. But he has been giving me the subtle signs that mean more than friendship. I have known him for 3 years and all this came up a couple of months ago. Recently, we had a formal evening with our company and when we hanged out, had a couple of pictures together and danced together a lot. We got really close, but nothing happened. I know that's because the both of us are confused. He is also in a long-term relationship and we are not used to liking someone other than our partners. I know this because many woman are attracted to his looks but he never had anything with either of them, and as for me, every man that came up to me in the past 4 years I turned him down. In him I see his good an bad sides i.e. I don't idealize him, I see him for what he is, and I don't notice his looks, I am more attracted to his way of life and thinking.

I am very confused about this, first of all because this is not some stupid love at first sight thing, I have known him for some time. Second, I see every side of him and I don't mind what I see even though those things have always bothered me with guys in the past. Third, I am in a relationship and so is he, and I can see that we are attracted to each other but because of social and work expectations we remain professional in the presence of others and take up private conversations when completely alone. He even walked me home one day so we could talk even though he came by car. He has also made some projects lately that involve us working together-very frequently. Only one of my friends knows about this and she says it is too obvious that he likes me (she also works with me so she started paying more attention to him and me) and that our current relationship is dangerous. She also noted that he has never been like this, that he can't refrain himself from being in my presence.

I am afraid at where this is going, really scared about the potential and the consequences. But the way he smiles and looks me in the eyes when he sees me or when we touch is overwhelming. I would really hate to cheat on my boyfriend and somehow I have this guilt that that's exactly what I'm doing. Mind you my boyfriend still treats me good but I just can't even look him in the face anymore without knowing how much pain I can cause him with this. Has anyone been in a similar situation? Any advice as to what this looks like, does it have a future and is it worth the risk? I really need any kind of advice, comments, thought on this situation...