What do I do? Is this something I shouldn't worry about since it is online only? I spied on his computer so I really don't want to tell him because he may start being more careful about what he does online. I want to know what he does behind my back. What do I do?
I would monitor his computer usage for a while. My wife found that I was surfing Ashley Madison, which I was but I was not a member so I could not contact any of the women. To be honest, I was just curious to see what is out there in the dating scene, not to hook up with anyone. It was interesting and I'll admit, a turn on to check out the ladies, but again, I was just looking. If he is having actual communications with other women though, its a big red flag.
If he went so far as to SUBSCRIBE to an online dating service, let's not fool ourselves here. He is on the prowl. Confront him about it and ask him he wants out of the marriage. The truth will be in his eyes so pay attention.