My Friend...

One of my friends told me that I didn't need to share my food with her. I thought that I didn't have to anyways since I wasn't going to give her any food. Then a few days later one of my other friends gives us a huge chip bag to share, I didn't like that kind of chips so I let my friend that said I don't have to share my food with her have it. Then the friend that gave us chips pulls out doritos and gives it to us, I take it but my friend holds on to it.

"Uhh _ _ _ _ you already have chips?"

"Yeah but she want's us to share"

"But you have chips?"

"Oh come on you NEVER share with me, I've shared with you plenty of times!"

I've given her $5 because she forgot some, tried to comfort her and this is what I get?

Honestly In our last period class I go and share my slideshow with one of my friends. She comes up to us and asks if she can present to my friend too. I tell her no, and she argues so I argue back. Then a guy starts screaming at us to shut up. And then she starts to get upset and goes to her desk. I put away my laptop and the bell rings. I see her crying and ask her whats wrong. She tells me to go away and leave her alone. My friend passes by and I ask my friend to comfort her. We both stare at her crying and then my teacher comes in and starts to get mad at ME! I honestly don't know what to do.