Re: I'm too dumb to understand wife
No, you are not nuts, and you are not to dumb to understand your wife.
Have you ever talked to your wife about this problem, a sit-down serious conversation? There are lots of things that could cause a woman to act or react this way. Previous sexual abuse or trauma, physical abuse, a bad relationship with first husband, being raised in a family where emotions were not spoken aloud or shown physically, hormonal imbalance, the change of life, etc.
It's probably well past time to sit your wife down and have a very frank and honest discussion about her past, her past relationships, her past sexual relationships and sexual history the way she was raised to feel and discuss emotions, these kinds of things.
There is something in your wife's history that is making her act this way. You said she's done all the medical testing and that's okay, so you need to start looking deeper. But also, be aware, digging up emotional/physical trauma is not always an easy thing. Once these burried feeling of your wife's are unearthed they'll need to be dealt with.
I hope that you guys can get things sorted out and she'll be able to come out of her shell and realize what a loving, caring guy she has right there in front of her. Try to be patient and gentle with her and help her get back to enunciating these feelings to you. Don't let her blow this off as something unimportant, it is an important part of your relationship....you've went far too long without the closeness and intimacy that you deserve.