I understand where you're coming from OwnIt. DB theory is all about doing something different so if T0 can't avoid falling into the same destructive cycle then I get why it might make sense to consider something else. And regardless of what she does we all agree that letting the marriage go in the sense of dropping the rope is the key to sanity.
I get nervous around the slippery slope of doing what gets you out of a difficult situation into a spot that feels better. This is eerily similar to the path that a WAS chooses. Right/wrong don't matter anymore, I don't want to feel this way anymore, I want out of this spot. There is a DB way to drop the rope, and no where have I seen separation suggested by a DB coach as a way of deescalating the situation. It may seem worse than a negative cycle, but DB is all about her breaking the cycle. The adversity in the current situation isn't going to be forever, it's going to be until she surrenders to God's will, let's go of expectations, and decides to dedicate herself to doing her part regardless of what she gets back.
By the way T0, there is a three part series on YouTube called Marriage Expectations by Andy Stanley that might really be inspiring to you. Parts I and II spoke deeply to me. I must not have been ready for part III
I'll end with a thought...many that walk away from a marriage site the fact that divorce may be difficult but that five years down the road those that divorce are usually happier than they were at the end of their marriage. They say this like it proves divorce was a good move. I always thought that was silly, because of course they were better, they were in a horrible spot at the time. But likely if they stayed married things could've gotten better too, because they were at a rock bottom and learning some tough lessons. Time made things better, not divorce. I hope for T0 that in 5 years things are better and it doesn't cost her marriage. But in the end we are ALL in her corner and wishing her strength to make tomorrow a good day and faith to know that there are good things ahead regardless of what happens around her.
Me:38 XW:38 T:11 years M:8 years Kids: S14, D11, D7 BD/Move out day: 6/17/14, D final Dec 15