being young and buying a book

when I buy a book at the age of 25, I think about spending decades with it. It's exciting this marriage, beginning of a relationship. maybe i'll carry it with me when i travel. maybe i'll snuggle up with it when i am in despair. but what will i think when i am 65? is that why there are so many old people at the library: because they can't bear to buy a book knowing there isn't a lifetime together?