Trust me. I just got the hang of this a few days ago and I still screw up.
Please be truthful to YOURSELF. Identify what made the marriage go wrong on your part(NOT His), fix what you need to be happy with YOURSELF about that. You can't do his part, but you for you can. Once YOU are happy... then everything else will fall in place whether marriage ends or begins anew or you move on. This is NOT what anyone wants to hear, but it's truth.
2x4's are good, but they are only to make YOU think clearly and rationally about YOUR reality.