@BirdDancer: And thank you for bringing up this topic. It's something I've been thinking about lately.

In my case it may also be related to trauma. I have problems trusting and connecting to people as a result of childhood issues, and the daydreaming might be a way of coping with that. I guess that's why I originally attributed it to the schizoid features. But when I'm feeling good the daydreams can also take on a positive and creative quality, so maybe the trauma-related part is only one aspect of it.