None of My Business?

Why do I snoop?

I snoop for a couple of reasons.

1. I'm curious if my husband will stop looking at, commenting on, and downloading pictures he sees on facebook of women in sudcutive poses, little or no clothing, etc. when things are going well between us.  I wonder if what we experience together in a good way makes any difference.  It doesn't.  I keep hoping it will...so far it hasn't made one ounce of difference.
2. I'm curious if he is trying to hook up with other women via messages on facebook or in his email.  

Those are pretty much the two reasons I snoop.

What difference does it make what I find if I do nothing about it and continue to torture myself with his findings, with his downloads, with his messages, with his comments of perfection - oft times sexual in nature?

Why the hell does it bother me?

And if it does bother me so much (and most of the time in these past six and one half years it  has bothered me), WHY DO I STAY?

This is what he has told me:

1. He loves pornography.
2. He thinks of it as art.
3. No one is going to tell him what he can or can't watch.
4. He is never going to stop looking at it or commenting on it or saving it or having it in his life.
5. He defends it with his life.
6. He gets angry and defensive about it when I bring it up and ask him if he would consider stopping.

The big question is this:

•  Why do I think that what I want doesn't matter?  That what I want is inconsequential?  That I just have to accept it?  That when he says he is not committed to our marriage (unless a few things change on my part), why do I stay and accept that?

Is it the money or lack thereof on my part? 
Is it that I keep hoping he will change?
Am I looking the other way because there are so many other great things about him that discount the porn, flirting, comments, etc?