When a friend moves away, you find out which parts were the friendship and which parts were just the bus stop.

A lot of closeness is built by proximity. You sat next to each other, you walked the same way home, and the talking happened because you were already there. Take away the shared geography and what is left is whatever either of you chooses on purpose. That is not a sad discovery. Some people were good company for a stretch of your life, and that was the whole deal.

If you want to keep one, make it deliberate rather than hopeful. Put a call on the calendar instead of waiting for a text, and expect to be the one who reaches out twice in a row sometimes.