Here is how i get the ending (spoilers)
I think that the whole last scene from him visiting her is the dream he was talking about. Because just like he said he woke up after he reached for a kiss, which is how the movie ended. And the two suns (as well as the earthquake) show us that it is a dream. So I think that by the time the movie is over they are still apart from that last break up, but this dream could be a wake up call for him to go get her back. We may never know if he actually did and if he succeeded. Also I think that is the only scene in a different universe. Everything else was taking place in the course of 6 years and everything fit chronolically and made sense. Also (that may be a bit of a stretch) in the dream he says that in a different universe they'd be together, so maybe in real life they actually did end up together.. who knows. I like that the ending is open and can be interpreted in different ways.
Also I loved the movie and I'm not really a fan of romantic movies, so that says a lot.
(sorry if my english is bad at times)
P.S. My other theory is that her being pregnant is a lie, just like he lied about Sixth Sense at the beginning, so in the end he got that and that's why he went in to kiss her.