As a guy, I just want to say that I agree with lil and kett. If he "needs" sex and you aren't willing to provide him with the "real thing," then his only "honorable" choices are: 1. celibacy, with no complaining to you. 2. masturbation, with no complaining to you. 3. divorce.
Having virtual affairs crosses the boundary, to me.
Using porn as a masturbation aid does not cross that boundary, in my opinion.
But, it seems to me that there must be some room for compromise in your arrangement.
