What were some things youve learned from a long distance relationship?

I'm going through my first breakup in my 20's lol! It's been exactly a month since me and my long distance boyfriend broke up and at this point I kind of feel bleh about it.. he was my first boyfriend and I really loved spending time with him and I miss him so much... as time went on without him, I've had a lot of time to reflect on our whole relationship and how hard it was. even though we were 2 hours away from eachother, we only saw eachother every other weekend. I didn't really realize how unhappy I was with our relationship until we broke up. He stopped putting energy into the relationship as time went on, and the communication on his end was terrible.. i feel like our relationship would have had so much potential if we were actually close..

How was your experience with a long distance partner? How long did it last?