FYI, my H is similar. He moved out months ago and now wants me to sign legal separation papers solidifying that we have been legally separated since his move out date. My first reaction was no way - I didn't want him to move out. But if I don't negotiate legal separation, he'll go straight to divorce.
And once I agreed to talk about the legal separation (maturely, calmly, with as little emotion as possible) he started coming around a lot more. Then he was more open and available to me. And he is putting in the agreement a commitment to MC. I can't figure out the craziness either. I figure it's a protective measure to cover himself "in case" - then he feels safer opening up? But no, you are not alone!