Hi

I'm kinda living a similar situation, except that he told me my feelings weren't shared. That isn't the case for me (but it's more complex than that), but maybe if you ask him what he feels it would help you to make a decision, don't you think so ?
It's "funny", cause in my situation, i felt the opposite when i knew he was certainly going to leave for a far away country, I felt like it would be the better way to enjoy the few i get (but as i said, my situation is different). I mean, if time is running out, you maybe should enjoy before there's nothing left... but i can copy it's very tragic

That kind of questions are so hard to answer, cause it's about what you're able and ready to bet. I'm stupborn so I always bet everything. But I might suffer very much. I'll pay the price, and I actually already do. But at least, I'll die with no regrets, only few remorses and some very beautiful memories at the end. I'd be you I would try, cause if we don't try we'll never know. But I'm not you, i just give my opinion.
What could help you, would be maybe to write down advantages and disadvantages of any of this both choices and help you with scales. Like "if i leave now, how i'll be hurted ?", "if i stay with him for those last moments, how i'll be happy to live those moments ?" and "If i stay with him and he left without the relationship to go on, how i'll be hurted ?"... guess i could help if you're a quite pragmatic person.
In any case, take care and never stop believing in future, i'm sure at the end it will be fine
