Doing anything with other women right now is a mistake in my opinion. If you are ending the relationship because that is the decision you made, then eventually there will be other women in your life. If you still desire your marriage to be healed, meeting up with other women is both a nasty game and hypocritical.
I agree with Sandi that much of what you're wrestling with is a matter of your mental/emotional attitude.
The reasons for focus on GAL and PMA with DB is to help you achieve a better emotional frame of mind.
You're looking for concrete steps that you complete and the result is a better frame of mind. It doesn't work that way. This is hard work and part of the reason it's hard is that you have to process a change in your thinking.
I do believe that at some point it will be necessary to have a brief conversation about the state of things. You need to know if she is interested in healing what's wrong between the two of you, or if she simply wants to play out things with the OM.
Problem is, I'm not sure you're are in a solid enough place emotionally to do that right now.
The indicator that you ARE ready would be your ability to hear her say that she wants to pursue things with OM, and you would be able to respond relatively dispassionately with the next steps (i.e. separate living arrangments).
Johnnie, this is something that you CAN do. The hurt won't magically leave you one day. It's a process. The first step is to accept it without allowing it to overwhelm you. To do that, you have to be convinced that you WILL survive and that you still CAN have a good life - with her or without her.
Blessings,
Bill
"Don't tell me the sky is the limit when there are footprints on the moon."