I completely agree with you that it is not the LDr's problem to fix on their own. Sorry if I implied that. I know that it would be very easy to fix if the LDr knew why it went but that does not change the fact that it is gone and that there is a problem.
That is something else that I have noticed about a lot of LDrs. They seem to frequently default to the "something is wrong with me" mode. As I have told my wife many times, I don't think about this in terms of there being something wrong with her personally. I try to make it about the situation rather than about the individual. I think it is difficult for LDrs to see that because, most of the time, in the backs of their heads they are thinking that there IS something WRONG with them, and so there is a kind of "hair-trigger" effect going on. It is not about right or wrong but about coming back together in a sexual/physical way.
It IS all about trust. Trusting one's self and trusting one's spouse completely.