Need Some Support!

Let me summarize this the best that i can. I met my boyfriend online about a year ago, we've been together practically since we first spoke. At first everything was going beyond belief, i had never connected with someone so well and felt so good. I had ended a truly bad relationship about a year before, and i can say that he helped me finish healing everything that was wrong. Until suddenly a couple of days into the relationship he would start disappearing. When he would finally appear he would just say he was really busy or create some really skewed reasoning's, that to be honest i wasn't eating up. It got to the point where once he disappeared for 2 weeks, i lost it and broke up with him. We spent a month or so apart and than he came back and things were looking up until he started acting that way again, To get to the point we had been on and off for about a year and finally when i was going to end it completely, he confessed to me that he suffers from severe depression. Up until that moment i remember him mentioning that he had depression at times, but i honestly didn't analyze it as much.... since i suffer from it but it's never gotten as bad as his. I went and did some re search, but no site online can help me with this! until i remembered EP. I feel grateful to have found this site and hopefully i can gain a better understanding so i can give him the best support i can. I love this person entirely i see so much potential in him and i know this sickness is eating him alive. I would really appreciate it if some of you guys can tell me if this behavior of concentrating fully on school and work is normal. He has gotten much better and communicates everyday now, but he's still hard to get a hold of sometimes.

PS: Since i am not there with him physically it's extremely hard to convince him of seeking medical help, i believe he's tried it before, but he didn't go into details. We are both 22.