LTL, I really sympathise with your sitch here. I was in a very similar, loveless, sexless, hugless, etcless M. I too didn't know what I was doing wrong and I kept trying things to bring the spark back. That's actually how I discovered MWD. I found her book 'The Sex Starved Marriage' on Amazon and ordered it to try and improve our sex lives. Unfortunately for my W the problems went much deeper than that and it wasn't something a quick orgasm could fix.
Since we were married, I stopped having my own life so much and my W and S became my whole life. I never realised at the time how much pressure this was putting on my W. Not only was she a young mother, she also had my happiness and wellbeing to be responsible for. This went on for about a year until she finally told me that she's fallen out of love with me. I think if I'm honest it was the respect which went first. She couldn't respect a man who wasn't responsible for his own happiness. I used to think marriage was about two people completing each other. I now see that it's about two happy, complete people complimenting each other. Nobody should be 100% responsible for your emotional state. That's why I believe you should let go. Give your W a chance to find herself and more importantly, give you the chance to find your own happiness and to grow as an individual.
My W walked out in January this year and I really worked hard to detatch. It was incredibly hard at first but I think the separation made it easier. We were very amicable when it came to visitation of our son and we continue to be flexible. At first, I still pursued. I called and texted her to see how she was doing and what she was up to. This was the wrong thing to do. It never improved anything at all. She was completely awkward around me still and I was falling deeper in to misery. Then, I spoke to a DB coach who really helped me to GAL and also on how to act around my W. I stopped the calling and I stopped the texting. When I went to pick up Wee Man, I basically got him and left without trying to make small talk with my W. I went as dark as I possibly could while still sharing parenting duties. It wasn't long before she started asking me what I was up to though. It was as if the roles had been reversed and she couldn't stand not knowing what was going on in my life. Well, since I was doing well at GAL, I told her that I was enjoying myself but kept it all brief. I still don't ask much about what she's up to. Sometimes she tells me anyway which is fine. I no longer plead, beg, or talk about our R. I have a life now that I'm enjoying but I've still not given up on my M.
My DB coach told me that I have to become friends with my W again before anything else can happen. That's what I'm working on now and although it's a slow process, I am seeing progress every now and again. We've shared meals together and she's started to confide in me again (something she never did for the last year). No, my M still isn't fixed but I'm not ready to give up either. Like you, I was in limbo for a long time. Mine was only a year compared to your 3 though. Things never really improved in that time. It's taken separation to start seeing improvements. It isn't always a bad thing. Just bear that in mind.
Kev
Me: 32, Wife: 22 Son: 2 Married: 2 years Separated: January 5th 2009
Sometimes you have to become lost before you can find yourself.