A lot of what you're writing could easily have been me writing if the dates went back a little further. It doesn't have to stay that way. I'm catching up a little here (lightning took me off the internets for awhile) so bear with me:
1. It's SO hard to do this in the fog of anger and frustration you're in right now (I know, because I tried) but when the moment is all wrong and the mood is gone and the sex is horrible, that's a great time to quit and do something else. If you're both fumbling and it's just awkward as hell, seriously, that's the time to laugh as loud as you can at the ridiculousness of your situation, give her a kiss and a big hug, and snuggle in to go to sleep. She may laugh with you, or she may not. She may melt because you didn't try to force the issue, or she may not. But at least this way you didn't have terrible sex that you hate to think about. Now, if it's not working because she doesn't want it to work, the way you describe, she may be testing you, or she may just not want sex or you or touching or who knows what? Again, this is a lot easier to say than it is to do, but that's the time to let go of her, tell her you're no longer interested and break it off right then. You don't have to let her toy with you like that whether she means any harm by it or not.
2. You asked BPickle whether she wasn't contradicting herself by admitting that it took her husband announcing that he was leaving to wake her up. That could be, but I think her point was that if he had made that decision to share his desperation with her before it overwhelmed him, they might have been able to change it together. I was luckier than BP's husband; I found the SSM book and then this forum. I had always promised my wife (child of divorce) that I (child of long, happy marriage) would never, ever leave her no matter what. People here convinced me that I had no choice; I was furious all the time and deeply miserable, and I hated my marriage. It was killing me. I loved my wife with all my heart, but I was sure she hadn't loved me for years. In truth, I was ready to leave, but I had made promises. People here convinced me that I had to tell my wife the truth and find out what she would do about it. That takes more courage than I thought I had, because I felt like once I said it out loud, I would be committed; I couldn't just glide along and pretend I could make it anymore. I did not announce that I was fed up and leaving. I told her that I didn't want to leave, that I loved her, but I felt like she didn't love me and our marriage was failing, and that we were on a path to divorce. I told her that we had to make changes or I'd leave. She saw that I was serious, and like BP, it was like she could suddenly understand what I'd been saying for years. The problem is that if you don't find a forum of people to knock you around and convince you that you're being a pussy, it's incredibly hard to work up the courage to deliver this ultimatum--and because you've been explaining your feelings for years with no effect, it seems impossible that it will change anything anyway. But it just might. And if it doesn't, you're not in limbo anymore.
3. I would read the SSM book if you haven't, but now, a couple of years later, I'm reading "Passionate Marriage" by Schnarch and I think it complements the SSM book well. SSM is the EMS approach--treat the life threats, maintain airway, breathing and circulation, and try to keep the marriage alive until you can treat it. Schnarch is more the long-term approach. I especially like the way he describes problems as being part of the stage you're in.
4. MWD talks about "Getting A Life." In other words, she wants you to get out and do things for yourself to increase your own enjoyment of life. Schnarch talks about self-validating--essentially the same thing, but his book is about three times as long and explains more of the reasoning behind why this is important. He explains that people who are "emotionally fused" depend on validation and esteem "reflected" from the partner they're fused to, which leads to being deeply in love but also emotionally disconnected--commonly expressed as "I love you, but I'm not in love with you." He makes a lot of sense, and that's a little worrisome, because although the book was written in 1996, I think a lot of therapists are still doing the opposite of what he advocates.
5. I would not assume she's having an affair unless she gives you some other reason to think so. An irrational, contradictory attitude towards sex doesn't require an affair to explain it (whether that makes you feel better or worse is hard to predict.) I sometimes think people leap to the conclusion that an affair is going on here because so many who post here have been through it that even people who have not suffered through an affair start to see them happening all around them. Try to find the balance between being blind (choosing not to see evidence of an affair) and being paranoid (choosing to see evidence where an objective observer would not.)
