chickenrun... Do you think he's fixating on you the way that you are on him? I'm sure he's not. Why do you need so much to know whether he feels the same way about you? I think you know that this isn't viable in a marriage and your husband would probably be angry if he knew that your friendship was on this basis (on your part, anyway).
I think you're obsessing about this man and over-analysing every nuance and, as you say, fantasising about him Why are you doing that? Ask yourself the question.
If the attraction were mutual - and nothing you've said indicates this - then so what? You're married. You're on a slippery slope to an affair and if you don't pull back now then that's where you're headed.
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To be honest, I'm baffled that you've (many of the posters on this thread) have had such a mild response. If you work on the premise that many women would consider that their husband/partner forming an emotional attachment with another person would be more hurtful than a physical affair then surely you can see that there is huge potential for damage with what you're doing?
I think that you're aware of the pasting that OW tend to get (unfairly sometimes), and have tempered the posts accordingly. I'm a bit sceptical because I get the distinct feeling that some of these 'EAs' have been physical.
I was an OW myself and it was a physical affair over a period of years. I read this thread and recognise some of the statements as my own. I think you're being hopelessly delusional and - I never thought I'd ever say it - but I'm a bit uncomfortable that this thread is almost a 'back-slapping' testament to mostly self-indulgent women who don't really want it to end.
I've replied to many OW who've genuinely wanted to find a way out. It's not really obvious on this thread.
You can end it if you really want to, it is that simple. I never said it wasn't painful but it would free you from this sleepwalking nightmare that you're seemingly so intent on not waking from.