Gonna have to agree with you here. OP sounds a bit controlling.

The first example he gave to someone else was about how she chews with her mouth open.

I mean, he can't even let her chew food the way she wants to.

The funny part is that he thinks controlling behavior is normal. He thinks it so normal that he cant figure out why he's getting pushback on this so he's looking for something to blame it on like ADHD.

The truth, OP, is that no one likes controlling people.... doesn't matter if they have ADHD or not.

If you don't accept people for who they are, you're always going to have unrealistic expectations for them that they'll never live up to. You'll always be wishing they were something they're not. You'll always be trying to change them... and you'll always be disappointed.