SMM hang in there. Don't give up yet! Your life is not a disaster. As much as there are weather seasons, there are also life seasons, and right now u r in winter. These seasond either make or break u, don't allow it to break u.
There are a lot of things that r happening in ur life right now, but don't give up. I know how it is when u r so down and under and u just wish anyone can listen to u and understand how u r feeling and ultimately give u a solution to your problems.

My 2 cents:
Your wife left coz obviously she was not satisfied with a couple of things. She came back coz she still wants to work on the marriage/ loves u. She might not be able to communicate her feelings to you becoz she thinks 'if u knew her u wouldn't ask'
or she thinks u would never get it anyway. Either way you have to listen to what she wants. By ur own admission she does say something to u....you say she blows things out of proportion....u r judging disrespecting her views and concerns. She is actually tellin u something but u do not think it is that important. Listen to her.
From what I understand abt 180s. Do more of the things that work and less of those that do not work.
By ur own admission u say u find it hard to lead or initiate. A woman wants a man who can lead and initiate without being too pushy or controlling. That can be ur 180