Husband Threatened to Leave, Don't know what to do

[MrBond]

"He wants freedom. He wants to be able to go out for drinks and me not nag him for going. "

Yep I knew this was going to be coming up since his admission to you about his new "way of life". Next thing you know he'll tell you why he's justified to talk to other women.

"Am I being annoying? Is this fine and normal for him to do? Or am I being high maintenance?"

Not at all. What you do is explain to him how his going out makes you feel. Follow the "when you do this....I feel like this". Just state it matter of factly and don't offer him any suggestions. Tell him that you appreciate the fact that he needs his nights out and that likewise you would like to feel valued the same way with your needs.