Oh and TIS I wanted to mention, but forgot!
Have you ever seen "Mind of the Married Man"? I've not watched alot but have seen the last few and the last one had one of the characters who keeps trying to bed a co-worker. She keeps professing all of this respect for the marriage. He keeps trying and one of his last comments was "this isn't about my wife or marriage, it's about you and me!"

I think men do sometimes view it like a seperate entity. Let me qualify with SOME men

He further said, "we're friends, we go out and have dinner, what's wrong with getting each other off?"

Looking at it from HIS perspective, it almost seems plausible doesn't it? In the real world though there are hearts involved and much more. Personally I could never hurt another WOMAN like that. It's forgotten there are always someone else's and if there are kids possibly many feelings involved. Not just something to pass the time and/or feel good.

Anyway, even though it has zip to do with the Sopranos, I think Tony uses a bit of that logic, it has nothing to do with Carmella. He takes care of her, she doesn't have to work, he buys here expensive trinkets and furs, what he does to relieve his stress is his business...So HE thinks.