I want to be clear that I'm not intending to

A: ask my wife to change anything about our relationship or "let me" try anything new

B: sleep with any "random crushes"

It's not even about just sleeping with others or sex in general, and the examples I gave are maybe not the best, there are others whom I know on a much more personal level that I also have deep feelings for. It's not purely lust, I know the difference.

That being said.. maybe you're right about the mid-life crisis part, that kind of touched a nerve, and I should examine that.

Maybe I'm just feeling stuck in my marriage and this is causing me to romanticize things more than the reality would be.