I will really feel like a bad guy if/when I have to move in the D direction.
Well, me too. And I never left H or cheated on him. It sucks but you've got to be in the here and now.
If you can handle the finances and the custody as is, than give it time. Only you can decide what is reasonable for you.
Personally, I see the way H is living and I feel humiliated. I stand to lose a lot financially if we get into it (I am dependent) but my sanity has some value too. I just don't want to be motivated by ego either...
There is no utopian solution and discomfort comes with the territory. It is a matter of which discomfort you can live with.