Wife going out with people I don't know

Hi - I work away from home for 3 weeks at a time not by choice but necessity. About 8 months ago my wife went to a school reunion and now she goes out with these new found friends from the past all the time when I'm not there. Guys or Girls. These are people from her junior years not senior so for the 25 years I have been with her I never met these people but have from the school she did her senior year's. My problem is iI ddon't know these people at all and she never makes the effort to introduce them to me on the week I have off. We are fighting about this quite a lot as I have openly told her I don't like it at all because I don't know these people. She says that I am being controlling and untrusting of her. Am I being unreasonable?

my advice would be to hang with these people when you are in town. be open and wine and dine. if a) she is resistant to this, or b) if you are not comfortable with these people, then have an open talk with her. but she is reluctant? this is a problem. either she wants her own space or there is a deeper problem. it is a difficult situation and you don't want to come across as paranoid. but you should tell her that if it is affecting you to the degree it is you need assurance from her, not accusation. and the only way to do this is to introduce you to these new friends. you won't intrude but you will know them at least.