It’s only natural to feel sadness. However, you’re focused on positives from the past and are nostalgic. Again, only natural. But don’t forget to remember all the mean, cutting insults and hurt he caused you. Don’t forget all the incidents and bad things that led up to this divorce. You are free of all of that crap. Relish in that and try to focus less on nostalgia. It was an illusion. Not reality.