I want you to know that I'm not saying to take this approach in order for you to give up. I honestly believe that if you can take some really big steps back (perhaps to give you two some breathing room)....and agree to behave with this type of minimal civility towards each other....it could begin to give you the foundation you need to build the R you want. I don't believe you can build the R you want....without that foundation.
So while I can see why you would say it's a cop-out, it's really not. It can be a way to put down that foundation you two never had. It depends upon how you choose to look at it. Sometimes you have to completely deconstruct something in order to rebuild it properly. You've already made some progress within your M as you've said....that progress shouldn't go away if you choose to take a different approach should it?