People treat you the way you let them.
As many have said it's up to you to change that.
I understand - i am married 36 years to wife who has become a functioning alcoholic. Bruises on her arms from falling down drunk and people look at me with daggers like I am the devil himself. "I didn't do that" I scream in my mind... My mind... slowly was losing it till I got it.
Maybe from Al-Anon... maybe from just time and experience, I have found some sort of peace accepting that I cant change or help her. I stopped feeling ... anything about it. If she becomes hostile or abusive, I say "stop it" forcefully and if she doesn't stop, I leave. And FEEL ok.
I have contemplated divorce seriously, not afraid of it anymore, and that seemed to take care of my co-dependance issues.
I am sorry to say that it sounds like your choice to remain on this merry-go-round or get off approaching. The woman you knew from long ago is long gone. She has been replaced by who you see now. If she doesn't change herself and you stay, your like will be filled with drunk episodes with all that goes with it INCLUDING infidelity.
The only thing that has kept me from filing is that she is loyal. I know this for a fact. I have checked. I have made my boundary quite clear.
Good luck. Hit the gym. Lift heavy and work out your emotional pain through physical exertion. Buy some new clothes, get a haircut, join a martial arts class and go out with friends. The only thing we can't get back is time... and the clock is ticking.
Life is best experienced happily.