As you know Muddle, middle ground and I are not well-acquainted. I'm either all fcuk you, I'm leaving or all up in your business (reminds me of that old quote, "I hate you, don't leave me").
I don't think it smart to say your 'only where we intersect' line, it's very cold (although I sure get the emotions behind it!). I agree with the others that you are still in an R until you're NOT. you know? you are still married. she may not be acting like it, but you are M. and until you are NOT (or you are done trying for a new M with her) I don't think you can stop trying on some level. But it does tend to make you feel like a dumba$$, to love and affirm someone who you feel is sh!tting on you in a very big way. Sigh.
When my H's A was going on, I came THIS close to changing the locks on him a few times, so I know the fine line we tread. And it's difficult like nobody else knows. And I feel for you. And I apparently ramble on your thread with no good advice. Listen to the others, I agree with them. How's that?
Forget the former things; do not dwell on the past. See, I am doing a new thing! Is 43:18-19
If it seems slow in coming, wait. It's on its way. It will come right on time. Hab 2:3