HER is an amazing piece of art. Walking out the screening, I was the least cynical about love and the most practical about relationship as I have ever been.
Is it possible for human to fall in love with an Operation System with artificial intelligent?
Yes, it is possible. Love is the magical thing. Anything can happen.
Is it sane to be in a relationship with an Operation System with artificial intelligent?
Probably not. There will be times in life when a hand squeeze or a waiting shoulder are what you need more than anything else.