I'm so sorry to hear of what you are going through, but you've come to the right place for lots of help and support. We'll get through this together, okay? Okay! We all understand your sadness, your fear, your desperation -- we've all been there.
First things first -- do not try to make your W read DB. DB is not for the WA (walk-away); it's for the LBS (left-behind spouse). It is very important for you to understand that you can't make your W do anything. The only person you can make do something is you.
It's also very important for you to understand that you need to take a scientific approach to this. Begin to utilize the tools in DB (180's, GAL, figuring out what is working, dropping the rope, etc.). Here's a link for you to check out from the board. It gives a lot of examples of men who were successful in DB'ing. Successful Men
Just hang in there, keep reading, do whatever you can to improve yourself FOR yourself, and keep your focus OFF of your W and ON you.
We all understand your sadness, your fear, your desperation -- we've all been there. 
