You seem to be grasping the idea pretty well. As you know i have been watching and reading for awhile but have taken a break, I needed it.
IMO you need to proceed as if the D is going to happen and you will not bust it AT ALL. It is not what you do b4 but how you conduct yourself throughout the entire process that matters.
If the changes are real than it does not matter how it ends up because you have changed for the better.
Being a single dad is HARD AS HE!! But it does have it's moments.
Be a friend
Be kind
Be there
And in the end you will be proud of how you have handled everything.