What would bring your marriage to the as happy as you'd like to be?

Fantasies, are fantasies. I wouldn't beat myself up, over it.

If you aren't actually, in contact with this man, then there's nothing wrong, per se, and of course, it doesn't mean you want to leave your marriage; the grass isn't always greener.

Take a look, at what's not so content about your marriage, what needs are left unfilled, that you'd like to work on, together, with your husband, that you can express to him.

Sounds, like you've got yourself a bit of a crush. It happens. It will probably pass, over time.