The only way I can imagine her being his daughter is something like:
Leia and Han have Ben first. A few years later Luke has his own daughter, might not even be known other than to himself.
Ben shows signs of being pulled by the dark side, so Luke thinks the same could happen with his daughter. Deciding to focus solely on Ben, he leaves his daughter with some force church people or whatever.
Luke fails from saving Ben, Ben kills his students and disappears, joins Snooke and creates his little knights gang. Luke leaves looking for answers.
Kylo hunts down and kills the people who are with Rey (seen in the vision,
it looks like they even tried to kill Rey to avoid having her fall into Kylo's hands, and Kylo saves her). Since it's a rainy planet, it's probably not Jakku.
How she ends up dumped on Jakku. Could be people who rescued her but had to dump her, and maybe Von Sydow was supposed to watch over her without getting too close so as to not put her in danger.
I think when Maz says "Whoever you are waiting for are never coming back", the use of "whoever" could imply that those people are not who she thinks they are, they aren't her family.
Whatever the case, I really wonder how VIII will start. If they don't start right from where VII ended, we'll never get to see Luke's reaction to Han having died, his reunion with R2 and Chewie. It was a bad idea to end the movie on that scene, it sort of fucked up the transition to VIII. Starting exactly where VIII ended would be really weird, especially since Rey would have to go over what happened, so they kind of have to leap ahead.