I've been selling some of my collection recently. While once I would have thought that selling my dolls would leave me feeling sad and abandoned, the reality is 180 degrees different. I feel happy.
Happy for more space? No, I haven't sold that many dolls.
Happy to have less responsibility? No, again, I haven't sold enough to feel a dent.
Happy to *hear* the joy in other collectors' messages? Yes, that is it.
It's like I get a vicarious thrill from the buyers' excitement. Like I am getting the doll all over again, all new. Only it's not the doll, but the shared experience, the pleasure of brightening someone else's day. I recall how I felt when I first received the doll and see that or a similar joy in the other person. That's the source of my "good feeling" - reflecting back another's happiness.