We teach people how to treat us. If we tolerate behavior that hurts us without addressing it then we are complicit. If we do address the behavior and set boundaries it is our job to stick with those boundaries. If someone crosses them and we tolerate then we are teaching that person that our boundaries dont matter. When you confront him about things do you tell him what it is that you really need? I mean aside from the obvious-to not have him involved with other women- but to you explain what you need? If you confront him but do not share your expectations then he will keep pushing the boundaries. If you do share your expectations with him and he still crosses those boundaries it is up to you to explain why that isnt acceptable and then set a consequence( I do not mean punishment like he is a child, I mean consequence as in what he will lose with you by his behavior). He needs to realize that you mean what you say. He needs to know that he is damaging his relationship and he needs to show that he cares about it enough to stop. If he doesnt and you keep tolerating it he has no motivation to stop. Why stop if he can have online relationships and still have his real life wife/girlfriend? He has the best of both worlds that way. You have to make it uncomfortable for him so he will stop. Personally I do not give many chances when it comes to situations like these. I view it exactly as if its infidelity. If he does not stop then its almost proof that he doesnt love you enough or take you serious enough to change his behavior. I am not saying this is easy but it is true. We are responsible for ourselves and how long we will tolerate discomfort in being treated a certain way.