This girl I "love" rejected me twice now.... what now?

[Thisguy]

Sorry for posting this again and again but I seriously want help.

Short version: Girl rejected me twice. I still kind of like her. I try to avoid her. She still makes many attempts to talk to me. I don't know what to do.

Long Version:
I am VERY sorry for this much writing.
So I am a 17 year old boy and this wonderful girl entered my life and she was considering dating me but she rejected me and then my feelings never subsided and about 5 months later, I basically told her that I'd like a second chance and she turned me down again (she said that she wasn't looking for a relationship but I think that was just her trying to make me feel better). and even now probably a month after that, I find myself unable to not think about her constantly.
I've started to completely avoid her in person though. we have a school activity where we see each other on every few weekends. But I avoid her cuz I don't wanna like her... But I do wanna like her... And the last 2 times I've seen her over the weekend, she's texted me like twice telling me that I should come sit and talk with her and our other friends. But I usually just make up some excuse and don't go over with them.
Us and our other friends have a 6 person group chat on Facebook where I talk to her a lot. And we text each other every now and again. Even just yesterday she texted me because I was Facebook messaging one of friends and she was hanging out with her so she texted me kind of relating to the conversation that I was talking about with her friend. And this is not in the day time, this is like past 1 AM. I didn't respond to the text though because I wanted to see what would her reaction be if I did not respond to her. It's usually her starting our text conversations, though.
I'm not sure if I should continue to avoid her anymore or what, though. I think about her every single damn day and it bothers me. I am actually kind of afraid that I am obsessed with her, but i don't stalk her or anything. Like I said, in fact, I try to avoid her... I am sorry for the long message but can someone give me their opinion on this?! What do I do now!?
I also feel like I am being very selfish and self-centered because I am avoiding her when clearly she wants to talk to me...
Many people have told me to just talk to her and figure out what's up.

[darth E]

tell her to piss off

[Cage]

cool story

[Damien]

Go on with your life.

[Amy]

Dude. You stop giving her the silent treatment. Many girls, including myself, will take that as if you aren't interested. If you really like her, then ask her how she feels. If she doesn't feel the same way, remember that "rejection makes men stronger". However, her signals (like starting conversations) point that she likes you.

[551]

make ou with her