Have you tried getting them to come to you? You mentioned that they don't... I didn't know if you've actively tried inviting them over. If you have invited them over, has it been for specific events or just casual, hanging out? Maybe if you call it an event, it'll seem more formal and they will come?

My family is the same way. They only rarely come over. Given my issues, it means we see less of each other than I wish we did.

Good luck with the situation. I hope you find a solution that works for you!