Thanks for the example, I have only seen bits and pieces of the Notebook, so I wasn't sure.
The bolded seems like the critical juncture and you gloss over it in your account. Now it's pretty hard to get a coherent picture from these kind of stories. You don't hear prosody, see facial expressions, you don't have a history with the people in the story--it's hard to judge. But if I'm being honest, this is kind of how you sound to me:
So I'm totally making it with this girl, we go back to her place, we're making a connection, she starts opening up to me, talking about her dead parents and shit, blah, blah, something about love, blah, blah, some more nonsense, and then BOOM! She's pissed at me.
I could totally be wrong, and I'm sorry if that assessment above sounds unfair, but I find people make sense, even if it's difficult to see that on first blush. The way you're describing her, she sounds positively insane. I'm inclined to think that you're missing something here.
It seems like that whatever she had said was very important to her, and you responded inappropriately (in her mind). I'm not saying she SHOULD have expected you to get it, or what she said made sense, but I get why she might be upset anyway.
The way I read it, she really was getting into you, so she divulged something super personal and intimate with you, hoping for a certain kind of response or reception, or maybe just someone who listens well, and whatever you did or didn't do killed the connection. Maybe you're not the kindred spirits she thought you were.
Does that make sense?