Ok, Vulcanized gave you a list of stuff to do. DO IT. Don't think about it, just DO IT. She needs space, less pressure, breathing room. If you smother her, instinct is going to lead her in one of two directions: flee or fight. Neither is what you want, so cool it.
Seriously, go re-read Vulcanized's post. Those should be your 10 Commandments now. I know it's hard, feels impossible to detach right now. But you have to.
If you want to fight for your marriage, to save it if it's salvageable, you have to be a man. Be strong when you're afraid. Be brave when panic strikes. It sounds like a cliche, but you can do this.
