i think the main reason ive been able to keep up a relationship with my friends from home is that we play dungeons and dragons together. even when we're all busy and end up not playing for like 2 months, having those semi-regular calls is huge. also, having that common touch-point of the game and our characters is great while our lives and other interests are going in different directions. ofc this is probably only applicable if you and your friends are nerds
