Sorry you find yourself here. You'll find no better place to try and get your M back on track.
Like Karen says, if you can afford it, talk to a DB coach. They are the best in their field and can give you the professional help and support that you need.
As for your current situation, IMHO, she's lashing out at you because you caught her messing around. It's a defensive mechanism. The old fight or flight syndrome. Continue to work on what you need to and as much as she rages on you, try not to react. Right now you're public enemy number one. You caught her being unfaithful and she's reacting out of fear. Fear of what her friends and family are going to think of her and fear of what it means for her.
When she gets to be like that, before she gets started, tell her that you are not going to be treated like that any longer and are deciding to see if SHE is worth it or not. Turn the tables on her for a change.
She's on the high of the OM. It's fun as a fantasy, but when reality sets in, she's going to have a hard time dealing with it.
M-43 W-40 2D - 9 and 5
Emotion, yet peace. Ignorance, yet knowledge. Passion, yet serenity. Chaos, yet harmony. Death, yet a new life.