SoftHeart, You both are now on your own individual travels through the MLC maze. Treat him as you would a friend, keep expectations at zero and affirm and validate his thoughts, feelings, etc. If he should return home, you will need to "think" of him as a roommate for now.
Your h has gone back in time to find the place where he was stunted emotionally. Once he's there, which I suspect he's at right now, he'll explore, experiment and yes, even exhibit some strange behaviors along the way as he continues to grow up.
What shall you do? Continue on w/your life, live it to the fullest. Pull out a sheet of paper and make a list of all of the things that you have put aside and start doing them. This is a very long journey and one that will require much compassion, understanding and patience. You will need to dig deeper than you ever have before for that "patience".
If he does return home, do not do everything that you have done for him in the past. If you are preparing a meal and wish to invite him to eat w/you, fine. However, do not become his mother during this time. He will need to do his laundry, etc. He sees you as a "mother/authority" figure and that's where some of the issues are coming from. He needs to grow up and learn to respect you as his spouse, companion and lover, not his mother.
As you travel the road here, you will learn quite a bit about yourself and yes, you will become stronger and wiser too. It's not an easy road, but we all are here to assist you.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.