What's up with Celeborn?

[A Little Green]

I was reading the LotR today and came up with the following passage where Celeborn says his farewell to Aragorn:

But Celeborn said: "Kinsman, farewell! May your doom be other than mine, and your treasure remain with you to the end!"

What is he talking about? I am not so deeply learned in Celeborn's personal history, so it just made me wonder whether he is just talking about the fading of Lothlórien or something else. Since this kind of little things tend to bother me, any help would be very much appreciated.