I have just caught up on reading your posts. I feel for you bro and can relate in part to how you've contributed to your M woes over the years without knowing what you've done. My W and I have no kids either and I have made many mistakes in our M.
But I totally agree with LAbug that you can let yourself only take half the blame. We all bring our own crap to the M and your W doesn't sound like she has been prepared to take her share of the responsibility for what went wrong. It is likely so much easier for her to just blame you.
Hang in there, I can see from your threads that a ton of people here care about you and are along for the ride with you.
I just wanted you to know that while I don't know your demons that you brought to your M before I still think I get where your coming from. Hope that makes sense.
Q1
M: 48 W:49 M:16 T:19 No kids Distancing last 18 months I have no feelings for you (we should separate): Feb 24/12 Me voluntarily moving out: Apr 1/12 (Fool's Day!)