I honestly believe you can never tell if a relationship is going to last. In my own marriage which is going on 14 years I don't think of it as 'I'm going to be with this person forever.' Instead I think of more like 'I'll probably be with this person for the next six weeks. Then I'll re-evaluate.'
I have piles of poetry books in the bathroom on the stairs everywhere. The only way to write poetry is to read it.