Blindsided

[evolve35]

Approximately 5 weeks ago my husband of 4 years broke down crying and told me he was sorry but he wanted a divorce. He states that we are disconnected, he knows we can no longer be happy together, he waited too long to tell me and that he won't change his mind and he just wants to be ALONE...
What really happened... he started out saying he wasn't sure if it was a phase but that while he finds me attractive he no longer loves me. Then I did and said all the wrong things, arguing with him about how we haven't even tried marriage counseling etc. until I pushed him right out the door within a week. He was then DEFINITE that he wanted a divorce and he wanted it YESTERDAY!
You see, we have been married 4 years. For the past 3 of those 4 years, I have been in a medical residency training program that has kept me from home for long hours, weekends and overnights. Sure, we have had our problems with communication and times when we argued a lot, but no other major problems. My husband is very sensitive and in retrospect, I think he started pulling away about 2 to 2.5 years ago... shortly after I got the position. We work at the same hospital and I thought he could/would understand my time committment since he went through a similar, but less intense program. Instead, I think it ate at him that the job got most of my attention but wouldn't dream of telling me this. He knows my bosses and I think he didn't want to lose face by admitting he couldn't stand it.
The signs were there that he was unhappy but I had my head in the sand where he was concerned. I kept looking for the light at the end of the tunnel as the residency is over in 1 year. Sadly, I was doing this residency for the two of us... now it is fairly meaningless to have this without a husband.
Within a week, I got Michelle's book and started divorce busting. We have to see each other at work at from time to time so I have made every interaction as positive as possible. I am doing the 180 as I am sure he will file for divorce, he doesn't tend to change his mind once he starts down a certain path. He has at least slowed down and started to realize what all is involved in a divorce as he had clearly not thought through the details. He hasn't mentioned divorce papers now in a couple of weeks and hasn't yet filed. I have been working on myself like crazy. I run almost everyday and while I wasn't overweight, I look better than I have in a while since starting to exercise. I also bought a motorcycle something I used to have and had forgotten how much fun it actually is...! This clearly surprised him and he was curious about it.
We are now friendly and he sent me several text messages last night about his new TV- we were best friends so naturally he wants to tell me about his new excitement...
So the question I have... what do I do about responding to him right now? He has not changed him mind, his communication is mainly about himself as previously described.. he doesn't care much about me... it is all about him right now.
I want to keep being friendly but if I am really going to do a 180, I feel like I should probably start pulling back. It has only been a week or so that he have been this friendly though so I feel unsure. I want him to know that it is safe to talk to me and he can expect a pleasant response.
I can't believe the range of emotions I can feel in the course of only one day. From anger to shock to relief to pain and back again.
I feel like someone has abducted by spouse.
Thank you to anyone that read this entire post. Wish I knew what was going on inside his head.