sorry posted before I had finished. I wanted to say that I didn't wish to sound mean or unhelpful, although I am not sure you are actually looking for advice.
A marriage is probably many things to many people but seeing as you have been having difficulties judging by your signature line for 7 years and given that you are 50 years of age I would think it is time for a radical rethink.
maybe your style of writing leads me to the wrong assumptions and I do wish you well. I realize that you must be an extremely private person but surely here of all places you could open up and show some emotion,love anger,frustration, maybe that is what your wife is looking for from you ?