I know that what you're trying to accomplish by all this is to stop the D. What do you think not talking with him over the D papers will do? it may not stop anything. I think alot of them do the "friends" thing. I know that some people are capable of it. I'm not sure I am. You are spinning b/c this is all so new to you. I've been at this over 2 years. While my H has not had me served or proceeded with D. He will. It's what he wants. i can't stop it. I have told him I won't help him. I think he's thinking that with enough time, I'll come around and even be willing to do it as cheaply as possible (one or no lawyers involved). Truth be told though, we don't know what they are thinking.
With regards to your D4. That is really up to you and I know esp now it's a really hard call. Is is good for her, sure. Is it bad for you....sounds like. Yo have to take care of you before you can take care of her (put your own oxygen mask on first...).
I wish I could tell you I have some answers (I don't) even just for me. I still don't know what the heck I'm doing. I say and do things that may not be DB, but they seem to work for me on some level. You're just so twisted up right now, you can't hear your own thoughts.