SMM23 - oftentimes when there are only small embers of the relationship left, the temptation is to smoother the WAW in an attempt to show her how deeply you feel your love and commitment. This unfortunately usually backfires and extinguishes the remaining life in those embers. In implementing the DR strategies (which Sandi did a superb job listing), you give those embers air to breathe so that they can come back to life.
As you focus on backing off and giving your W space, also focus on GAL (getting a life). Addressing the depression, finding something you truly love to do (whether or not you are paid for it), picking up some new activities and hobbies and perhaps even taking another look at your grief for your lost child - these are just some suggestions (I am confident you can come up with more) to focus on becoming a better you.
In life, the crappy times are often the ones which wake us up to areas in our lives that we have long neglected. In a strange sort of way, they offer us opportunity to grow and become better and stronger in ways that a serene life cannot do.
Is there hope for your relationship? Absolutely. But most importantly, there is hope for you. Hope that you can become the man you want to be - the man you lost so long ago. All of us here cheer you on and look forward to hearing more from you.