The hunt ends when you find the right one. Will you still be attracted to other women? Sure. You're not dead. But as Paul Newman once said, "why go for hamburgers when you got steak at home?"
Some guys do run around on their spouses, other beat theirs too. Neither are what I'd call a man.
PATRICE O'NEIL ON CHEATING:
Your old crush is just you looking over the fence and admiring how green the grass is. She isn't the issue. The issue is that you are in a relationship you don't want to be in. Not wanting to end a relationship because it would be a shock to both of you is hardly the reason to keep it going. Likewise, if things have fizzled like you claim I doubt you ending it will be as devastating to her as you might think.
As for what would a man do. He'd either stop letting his mind stray to other women or he'd break up with the one he's currently with and not interested in (thereby freeing her to find someone who is).
+1, you're either a 100% in or 100% out, there is no in between. On a side note my grandaddy would say "the grass may be greener, but it's just as hard to cut."
Plus, grass is grass. Someone is tired of mowing that lawn too and lookin at your lawn with envy. Someone is tired of mowin Natalie Portman's lawn, someone is tired of mowin January Jones' lawn, etc, etc.
If I had an opportunity to mow either of those lawns I'd buy a mower...
A wise man once told me "The grass is always greener because there's a lot of s**t spread around over there..."
A large part of what keeps my mind from wandering too far is that what I have with my wife is a reality while whatever might-have-been or might-be is strictly conjectural. We have a life together that we're actually living, instead of a fantasy. We have real accomplishments and serious plans, not mere imaginings. In short, I'm too busy living life with the woman I married to give much thought to this or that other lady.
But this required commitment, closing off other possibilities to fully place myself into one relationship. You haven't done that. You toy with the idea, but that's all. Your thoughts of settling down with her are only thoughts, not plans you're working toward realizing. In short, what's needed is action. Put crudely, shit or get off the pot. I don't know your situation, but it's time to either start planning a future with the girl you've been with for over three years, or to go your separate ways.
Buy a ring or break up? Not quite, but after three years you should be thinking about it, not as an idle fantasy, but as a real decision to make. What, if anything, would need to be done before you could settle down with her? How do her goals for marriage, family, career, etc... comport with yours? Right now it sounds like your relationship isn't going anywhere. It isn't ending, but it isn't moving either. Change that. Either move forward, or end it.
If you love the girl your with, but not enough to not move the relationship forward (marry her) and/or stop having fantasies about others. Then set this girl free. Your not crazy in love with her. Set her free to find that for herself. Also, free yourself for the same reasons.
Sex doesn't last. Relationships built on a deeper connection do. Call me a hypocrite since I'm single and I have no desire to change that anytime soon, but I've been around the block a time or two. You'll know when you've found the woman you want to spend the rest of your life with. The foundation of your relationship with her is going to be far more than mere physical attraction.
If/when one of you stabs the other in the back is an entirely different can of worms that I won't open here.