Hi James. First let me say that your M can be saved. Based on what you've told us, I don't think it's too late. With that said, I want to give you a word of warning so you can brace yourself. When a W tells her H that she's unhappy it's usually the first level of more to come.
There are signs that point to my reasoning here (other than I was a WAW and recognize some things). She isn't showing any evidence that she wants the MR to improve, right? The only thing that you've been able to tell has been better since "the talk" is conversation. But when a woman tells you she isn't happy, although she hasn't said the D work, she's talking about S.....which is another level. She isn't talking about what she wants. You asked her and she doesn't know? She know. You suggested C but she doesn't want to do that either. You are the one trying to put the wrong back on right.....but she's not wanting to do anything to get help? And, last but not least, she doesn't want touching. Even the smallest, like holding hands. That is the biggie right there!
I'm afraid she might be an almost walk away wife, if not already. If you have not read Michele's article here on her home page, then read The Walk Away Wife Syndrome. It will help to open your eyes to how your W is feeling.
The other sign is her not having a desire for sex since the last baby. Her doctor should have discussed this with her after the baby was born, but none of my doctors ever.....EVER asked me how was my sex drive. Her hormones could have taken as serious dive after giving birth to the last baby. Also, I suspect she's been depressed for a long time. When the hormones are flat and your busy raising a family, depression is usually in the mix. I was depressed for so long that it became the norm for me. But it's not normal and it's not something that one can always correct without medical assistance.
All of this together, added to a MR where the H isn't feeding her emotional needs, is usually a S or D waiting to happen. Don't blame yourself for the entire breakdown of the R b/c these other factors are hindering her happiness. However, the danger lies in her deciding to find whatever it takes to make her feel happy.
I'm very concerned about a young woman who would split up her family...especially when she has 3 children. So many women have a fantasy of how much better their life would be without the H around. But a fantasy is all it is. Some women allow this fantasy to build through the years that they're unhappy. The bigger the fantasy....the harder it is for her to grasp the reality of the situation.
So, here's what you don't do......don't talk about the R. If she brings it up, then you listen to her while you are looking straight into her eyes (that lets her know you are "really" hearing her). The MR will not be fixed with you talking to her about it. You will want to.....worse than anything, you'll want to talk about it, but don't bring it up. If you do, it will pressure her to answer you with what you don't want to hear.
Don't take her emotional temp to see how she's feeling about things. Don't pursue her. Pursuing would have worked at one time, but now you need to back off. Pursuing puts pressure on her and that causes results you won't like. Don't have expectations about anything where she is concerned. Don't try to read into her words or actions. In other words, if she smiles one day, don't think she's ready to reconcile. Don't move out of your bedroom. Don't move out of your home. If she wants to leave the bedroom or the house then that's her decision, but don't let her try to get you to move out.
Remember that you are the leader in your home. As the man, the husband, and the father of three children, you need to show maturity, honor, strength of character, and dignity. I could throw a lot of other things in here, but hopefully you get the idea.
Many LBH's give over to whatever the W wants, thinking that it will help the R. However, that isn't always what she wants from him. She wants a man who she can respect. A woman cannot love a man she doesn't respect.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!