boyfriend leaving in two months for military

So my boyfriend of two years is leaving for basic in two months. And then after basic going to BUDS. I'm having an EXTREMELY difficult time with this. He's not even gone yet and I'm always breaking down and crying. It feels like my heart is literally breaking. We are going to stay together. Everyone says we can't make it. And I don't want to believe that. Because we love each other unconditionally. He's not a fuck boy. He's not someone just passing through my life. I can genuinely see a future with him. I just hate having to wait 5 years to be with him. Anyone have any ideas how to ease the pain? I know this may be stupid but I feel like I'm going to die. But I already suffer from depression and anxiety so him leaving does not help at all. Please help.