He is joining the military

I been dating this guy for a year, it does not seem like much but we known each other longer. We were best friends for several years before actually going out and have a complicated history. I have never had a relationship like this one, he is my everything and I am emotionally dependent on him. When we started dating he had told me how much he wanted a career in the military. Before getting into a relationship with him i was in a never ending war with my parents because they never let me do what i worked for, like go to a good college or study abroad. So when he first asked my opinion about the situation i couldn't tell him not to go when i knew how bad it feels to not do what you want. When he signed the papers to join the military i cried like a baby for 2 weeks, and i couldn't focused on him and his company but instead in the fact that my time with him is limited. As time passed i fell more for him and i couldn't control my feelings knowing that won't see him for a long time. We have talked about it, if we are sure that we want to wait for each other, but we are to attached to break up. In around 4 weeks he is leaving and i wont speak to him or see him or have any contact with him for 3 months the he will come back for 10 days and leave and talk to him only weekends for a month, then we can communicate freely and he will visit every three months for 4 years. Just thinking of that breaks my heart and makes me feel so weak, i don't know if I am strong enough for this, but i love him too much to break up with him. I won't find someone like him or have a relationship like this one. I just cant handle it anymore and i have been crying non stop, but he cant back down now, and he is very excited about it. We talked marriage but i also have goals that i cant let go of, and this is the hardest thing ever, cause i love him very much. Sometimes i just want someone to tell me that we will make it and that everything is going to be fine.