It was so easy to make friends during my undergrad because I lived in the dorms. But I lost half of them due to a messy situation with my ex girlfriend, and the other half doesn't live in town anymore.
Now I'm 22, working on my Master's, and I feel like I have no one.
One last tip, try to organize an online game night with your friends who moved away, discord has a couple built in and I highly recommend boardgamearena.com
Oo good idea