@val1978,
Lots of things going on here. In no particular order -
1) You've got a crush on someone (at work? I'm gonna go with that). That happens. People get deeply involved with a coworker because they're working on a deadline or whatever. Plus you see that person at their best or near-best a lot of the time. After all, we put on nice clothes for work. We shower. Women wear makeup. We say please and thank you and all of that. But recognize it for what it is. You (usually) don't experience people doing all of the intimate not so wonderful things we have with spouses and long-term relationships. E. g. farting, hogging the remote, leaving the toilet seat up, dirty laundry on the floor, etc. etc. fill in your pet peeve here. Take away the unwashed dishes and whatnot and your husband may very well be seen in the same light as this gal at work. The whole situation sets it up for you to idealize someone. So step back and understand you are being unfair, as anyone you live with cannot possibly measure up, in pet peeve areas, to anyone you work with.
2) Your husband and looking at other women. I take it there is no touching involved. I gotta say, I find looking to be way down on the alarm-meter, but maybe that's just me. I look, my husband looks, everybody looks. Perhaps he is more obvious than most. And if he is unfairly comparing these women to you then that isn't very nice at all. But understand it's the exact same species of unfairness as your work crush. Those women at the beach or wherever - he has never seen them with the flu. He has never had an argument with them about whose turn it is to change the cat litter. Etc.
3) Your husband looking at porn. Slightly higher on my alarm-meter but again, I find it to be minor but perhaps that is just me. I know it bothers a lot of women. But a lot of women do not get that the vast majority of men look at porn. There is a very, very good reason why porn is THE killer content online. 'Cause it's got a nearly inexhaustible audience. It is a visual stimulus thing. Violent porn is an issue as it can be a sign of something else (e. g. getting pleasure out of suffering). And if it is being watched while you are willing and are being ignored, yeah, you've got a damned good reason to be pissed. But if it's watched when you're not around - well - hate to break it to ya - but lots of things happen when we are not around (who do you think ate the last of the potato chips?
)
4) Attractions to others of the same sex - I am not going to tell you this is garden-variety because it is less common. Certainly if attraction turns into touching then you've got a major problem on your hands. Has it? Does it threaten to do so?
I personally think you're both kinda bored. And you're looking for external stimuli. Have you tried working on these issues together? I mean really working on them. You say he is your closest friend. Then fight for this relationship to work out.