Wow, these are a good place to start to look at this stuff. But I did not ask those questions for you to answer here, nor to even answer right away, but to ponder them for yourself as you work on healing the relationships you have with your wife and with yourself. Things like this are deeply personal, and deserve careful investigation and reflection, more than one can do in just answering an anonymous person on a message board. It brings up issues surrounding self-esteem, sexuality, intimacy, letting one's guard down, possessiveness, love, expectations, sharing who you are at the core with someone and letting them share who they are. "Who am I? Who is my wife? Who are we together?" and so on.
And this is the nugget:
Originally Posted by RobertCourage
A relationship . . . makes me feel like I am a failure as a husband.
Why not take this as a start and continue in your therapy together, is my suggestion.