Just read this thread. What comes across to me is how stressed out your H is. Any kind of pressure seems to freak him out a lot. So, as many have said, back off the phone calls and try to be more in sync with his one or two points of contact a day. That really is quite a lot (well, compared to my sitch it is). Remove as much pressure as possible, but add some mystery to your life. Also, be supportive and don't criticise or respond negtively, unless you feel very strongly.
Your H is very sensitive to any feeling of being pushed in a direction where he doesn't want to go. If he has a direction, and he's certainly not sure, it's towards D. So, anything that is thrown in his path stresses him, really stresses him (I know you are very stressed too). As someone else has said, he's clinging to a mantra that things will get better once he sorts this out. This is his hope. However, what strikes me as strange is that it feels to me that there must be more stress factors than just your R. Is there anything else going on here or was there?
How did this start? What did he say? How did it come out? Do you know anything about the OW? Who is she and what relationship has she had with him in the past, if any (don't snoop though please).
Hope you're doing ok.
Max
Me 36 W 37 Bomb (Easter 07) Sep (WAW July 07) "It's over" (end Oct 07) T10.5 years, M2 (before bomb)