My feeling is that when you are married even a perceived problem is a problem. If either partner is bothered by the behavior of the other it effects both and can't be ignored. With all the wonderfull oportunities on the internet, it's a drag that he has chosen this avenue and it will be a tough one to break because it's just a click away. Like any problem (addiction) it's difficult to deal with until he admits it exists.

I also think that if you don't have trust in a relationship there is not much to build on. There has got to be something the two of you can do together to replace the time he is spending on the net.