Take a break Yenk. Give your mind a rest. Its okay to say when you have had enough, and a break and rest on your mind is required. That way, you can focus on what you need to do.
I believe DR has some great suggestions, but I think it is different for everyone. For me, going dim, not dark, was the best solution. Making sure my H knows that I understand how he feels and why is good, but I needed to learn to say it in a way that portrayed to him that I did understand without overwhelming him. Look at things from her eyes. Its not real pretty, but look at you through her eyes, and then try to think what she would like to see different, and if that is something you are willing to do.
Your sitch is really hard, because there is an OM. But remember, jumping from one relationship to another does not solve problems, and your W will see that. You have to give her the ability to make her own mistakes. You cannot save her, you cannot correct her. You can just let her come to her own conclusions.
Pray. A LOT. I recommend Stormie OMartian's books, because she has taught me to pray in a way I never though possible. Most importantly, though, is listen. This may sound cliche, but with God all things are possible. You just have to have faith and believe. And remember...there is a lesson to be learned in everything. Find out what the lesson is.
Im still standin better than I ever did looking like a true survivor feeling like a little kid Im still standin after all this time and Im picking up the pieces of my life without you on my mind..