I'm approaching 30 and beginning to think about marriage and I'm starting to find myself in a similar position. After graduating I moved across the country. I still consider my college friends some of the people closest to me despite, for a few years now, not being a part of their daily lives or having regular conversation .
We would have group video chats which was great, but they have become less and less frequent. Contact is quickly approaching yearly calls for each others birthdays. It's especially hard when you feel like the only person reaching out.