Mend this broken heart?

My best friend since fifth grade and I began dating four months ago. He was a senior and I was a junior in high school. High school was coming to an end and he was accepted to a college across the country. We had talked about long distant relationships very briefly, but it was generally about staying together even though we knew long distance relationships usually don't work. The second to last day of school was my last day for i was going on a three week trip to Greece with my family. We spent the entire afternoon together and we finished the what I thought was an amazing night with him dumping. I felt like I had been blindsided mainly because our conversations have been suggesting we stay together. Later in an email he said I had meant a lot to him and that he was sorry it had to end this way. One thing that somewhat irritates me is that he didnt even want to try long distance, but alas I know this is "puppy love" because I'm still in high school and I've only dated him for a few months, but I'm asking how to mend my broken heart from being dumped and losing my best of best friend