Why would a confident sociable guy avoid talking to a coworker?

Anonymous

I have a married coworker who is known for his extramarital affairs at work. He was supposed to train me but went out of his way to ignore me and sometimes even physically hide from me when he saw me from afar. Other coworkers noticed it and pointed it out so its not just in my head.

From the very beginning he was very disinterested, cold and formal with me which is very unusual for him since he is very sociable, charming and talkative with everyone else including new staff and strangers.

He encouraged me to approach him for all sorts of work related questions but in the rare cases I do he seems closed off, distracted and short. Why would he act like this if he is even known for being a bit too close with his female coworkers? I'm not fat nor am I ugly and I approached him very rarely so there is no good reason for him to be annoyed with me (I think).

Why would a confident sociable guy avoid talking to a coworker?
3 Opinion