Heh, it said "Ice Queen" under my name for a long time on here - as you can see, I have changed that now. My ex called me that because I wasn't showing him the emotions HE wanted me to show. Negative emotions kinda didn't count - as long as I wasn't being lovey dovey, then I was the ice queen.
TBH, once I made the decision, I felt free as a bird. I couldn't stop giggling for days, though I suspect that was a stress reaction in itself. After that, yes I can understand the heavy heart - it was not the loss of him per se, for me, but all that he represented to me at one time. Family, kids, partnership, companionship, in-jokes, buttress against loneliness, successful business etc etc. It's hard being single these days, especially if it not a state one is used to in adult life.
Mourning is natural and takes time. Even almost 3 years on, I still have moments (even days) where I kick against my present situation. For me, I wasn't just healing from that relationship, but from ones before that and way back into my childhood. To expect myself to get over the whole kit and kaboodle in short order was unrealistic. Be gentle with yourself.
And please don't think that how he is now is how he is destined to be forever. Who knows what it'll take for him to "get it"? It may be long after you have moved onto pastures new, but as long as one has breath in their body, there is hope. We cannot know the future. Deal with the here and now to protect yourself and your loved ones, however please don't think it is black and white, this is how it will be forever. The human spirit is stronger than you think. It is incumbent on us all not sacrifice ourselves at the altar of someone else’s issues.