IMO opinion, you have to do what best for you. Take care of yourself for you, go to the gym for you. My only question for anyone struggling in life is "Are YOU happy with who YOU are?" Maybe your wife feels the exact same way you do? There is nothing I like to see better than successful marriages and they can be such a roller coaster and some of the hardest work you ever do. I think part of it's success is 2 people that work at it though cause if it is only 1 chances are it will not last. I wish you the best .