Welcome to Lifesupporters, laki33!
I just want to concentrate on you because we can never change another person, ever! I've lived a long time and learned a lot about relationships along the way. The most important thing I learned in my marriage is to see what's going on within me and how I could make myself a better partner. The wisdom I have learned is to treat my husband with kindness, no matter what. I looked within and found tremendous strength there. I learned how to be my own person. Once that happened, I was set free being able to handle problems that came up.
Your wife is having a difficult time, too, and needs kindness no matter what. Sometimes one partner has more strength than the other at times, and vice versa. That's what relationships are all about..give and take. Right now she is taking from you and, of course, you feel hurt; especially if you see her with another man. However, once you find your strength and peace, you will be able to move on no matter what happens.
Talking to her on a compassionate level would get the best results, IMHO. If you are in any way provoked, step back, move to silence for a moment or two, whatever works so that you don't exchange anger for anger, hurt for hurt. Be the strong one no matter what! On each exchange that happens afterward, she will see how strong you are and how you don't buy into the anger, she will relax and you will be able to communicate more fully.
I wish you both the very best in working this out!