I had a sort of similar story about 20 years ago. I was 18-19 then, and it was a very strong love story for me. Since then I got a lot more experience. I think, some men are not good at expressing or even acknowledging their own feelings. They are sort of cowards, emotionality speaking, some of them, really. (At best, actually, becasue some of them just don't care and just enjoy)
So we, the girls, who are so much more sensitive and so much more in need of understanding and expressing things out, we have to be the true heroins in these sorts of story.
When he left me, he did not say he left me. He just had to move to another part of the country for his studies. It was terrible not to know his feelings -- although I had told him I loved him. I then realized that I got pregnant, and realized he was simply not reliable AT ALL. I had to heal my heart from stopping loving him (that came in the process of going for abortion... I thought, this a a father-less baby). That healing made me stronger. Being emotioannly dependant on someone we ccan't rely is terrible. I understand. I know.
You know what? He came back to me 3-4 years later, telling me I was the only interesting thing in his life. (That was his very words, you see, he could not even say "I love you"). By then, my heart was healed and I did not want to enter a relationship again with him, not because he was not so lovely, but because I knew he was a weak person.
Lizzie, I mean, be strong. He is weak. He is not reliable. This story is sucking your energy and life energy, not because of your love, but because of his weakness. Take care of yourself, don't let this happen to you. I guess you are young and lack experience.
Take care of yourself. Practice deep breathings, learn to enjoy life, the sky, the air, the water, all the treasures within and around at the present moment. Life is a treasure, don't entrust it to anybody else. Learn to appreciate it fully. MAybe you could practice a bit of meditation, or Tai Ci, Chi Kong or yoga. This will help you re-balance your energy and be stronger in the here and now, and in connection with yourself.