This song can mean lots of things , for example :
1.'it wasn't real' meaning Literally that it was just a dream, maybe an apocalypse kind cuz if you get to know this person your search is over, or ,your life as you know it, might be over
The way you put all your bets on somebody but it wasn't real love, just a crush.
Open your eyes just to realize that your partner fool you.
You just realize that this person was more than just a friend, and you trully care about he/she -maybe as a lover xD-
This new person you've just meet it's already putting your life upsidedown, breaking all your rules and he/she is even better than your archetype of a soulmate.
This song can mean lots of things , for example : 1.'it wasn't real' meaning Literally that it was just a dream, maybe an apocalypse kind cuz if you get to know this person your search is over, or ,your life as you know it, might be over