Everyone has been someone in this movie. You have been "that girl" or "that guy."
You've been the person rejecting, initiating, engaging, avoiding, stalking.....you have been them all.
Yes you have.
If not, then your life is boring. We all know what it is like to be in relationships that are amazing, and ones that are so awful you don't even bring them up when they are done. We all played the parts and been the characters.
I have been "that girl" and "that guy" (sans the married stuff). I have been the girl who is crazy about someone, the girl who is not so into you, the girl who is a flirt, the girl who is in the committed relationship, the girl who cheated (not at the same time as being seriously committed-I swear!!), the girl who wants to get married and the girl who just wants to be alone. I like that the movie left me sitting there, thinking, "who told you we think like that....." or, "I did that, yah, that was bad." Whatever it was, this movie hits a nerve. Ultimately the movie leaves your head spinning and makes you just want to not think, talk, or acknowledge relationships for another six months and it also leaves you laughing at how much white noise and drama gets filtered into every one's head when it comes to all this stuff.
My advice:
When you know you like someone, you know.
You will never need to wonder, need to hesitate to call, need to make excuses for them, etc., etc., etc.
It just happens.
This goes for guys and dolls.