Re: I don't understand why people fantasize when they claim they are "happy"
I'm sorry but I think this may have been discussed pretty thoroughly in some other posts, but here goes; Men do this! It has nothing to do with you and believe me, he is not unhappy with you but an active sex life stimulates the brain and fantasies, not the other way around. Women have trouble understand this but men like porn because it stimulates them visually and sexually. But, honest to goodness, when men shut the door on porn or fantasies, it's over - the book is shut - adios. Try not to let it bother you and I realize it might be hard to do, but at the end of the day, it has no thing to do with you. Try to be happy in your relationship and work towards that and drop this. That's the best advice I can give.
One caveat I have to mention, I am not saying that porn can't become a "problem" if used extensively or instead of a live partner. I'm not hearing that in what you've written but it's worth keeping an eye on. Good Luck to both of you!