I met this chick at a party after it was busted (we were over 21 so we were cool) and I spent the next couple hours taking care of her. At first, yeah she was drunk and that explains the affection I was getting from her, but it continued after she was completely sober. We ended up walking holding hands for 3 hours just talking about nothing and it was a great time, we finally got back to my car and took her home. On the way there she said we needed to hang out sometime and I said yeah.

but when she got out of the car there was nothing, not even a hug. She posted on my FB wall "hey thanks for the adventure and the pack of cigs ;)" but never contacted me after that.

The next day I ask her "did you find your stuff" in a message and she just said "yeah, it was in my friends car" which is to be expected I guess since she was just answering a question.

I'm so lost, I really like her too and I'm not sure she knows that. I didn't show her much interest except caring for her and a few flirty comments. What the hell do I do?

I think that it's important to know that you can't always get the girl. Sure you can up you conversion rate but you have to fail some times to learn the lesson. I went through your situation so many times that until I realized this little fact, I made no progress. So here is an opportunity to test some new ideas and learn to lose. If you can be open to the fact that you might lose her, things will get easier.
Now, from what I've learned, shooting a txt from time to time that doesn't require a response is enough to keep you in her mind, which is important. But if you can send a txt that requires no response, makes her curious and makes her WANT to txt you back, that's even better. For example: "nah, I didn't think so" or "saw something that reminded me of you today". Those can make her curious and want to know what is going on. If she replies, never answer the question. Just keep the conversation going. Also, always end the conversation and make sure she txt you last if you can.
All of that should help. Of course you should never forget to not get all clingy and txt/call her everyday and let her earn your attention. Finally, go talk to other girls and do the things that you always do in your life! Never make her a priority and if she wants to get together and you have something going on already, then keep your original plans.
The thing is that guys tend to make themselves too available and girls don't want that. Hope all of that helps!

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"I'm not a player, I just know how to quickly and efficiently remove a woman from my life when I figure out that she isn't good for me. If everyone has a soulmate out there somewhere, then I'm on a mission to find mine"