Based on a line from Evanescence's song Even In Death- "Even in death our love goes on, and I can't love you any more than I do".
It's not a very sad story, though if you're triggered easily... better not read it, maybe.
Our Love Goes On
It won't be too long now. Blaine knows it won't- the doctors has been telling him so for a while now. It's the end of his line. That's okay; he's not sad. Maybe he should be, but he isn't.
He has no family left, so that's okay, too. He won't be leaving anyone behind.
He never had kids, because Kurt passed away too early for that. His family is long gone- parents and father in law left so long ago he's not sure exactly when it was. He's pretty sure Burt didn't get to see them find the cure for cancer, and he's sorry for that. His brother and his sister in law passed a few years after both their kids settled down and had their families, so he's not sad for that.
His nephews and their children aren't very close with him, and they're already grown. They'll handle it- he'll leave them his money, at least the part he won't donate. But they will be alright, he knows they will. His brother raised them well.
So he doesn't really have something to live for, right? It's time to move on.
He thinks a lot about his brother in law, almost as much as he thinks about Kurt. He misses both; they both left so early. He's not sure if he'll ever get to see his brother in law again, but he hopes.
Kurt, however, he knows he'll meet. He hopes it won't take too long; that they'll have more time. He wishes that maybe in their next lives everything will work out. He wishes they'll meet when they're youthful and happy and grow together, like they almost did this time. He wishes it won't be long until he sees Kurt again. He wishes to be next to him. Maybe see him once, just once more before they begin their next lives, just to let him know all the things he never had the time to say and how much he loves him and how he'll love him in the next life as well.
When he dies, he's asleep. It doesn't hurt- or maybe it does, but he's already dead, so he doesn't care.
He takes to the air with all of his soul set to finding Kurt's, and doesn't stop searching until he's once again, in Kurt's arms.