My friend read my text messages... please help?

Well, she's giving me the silent treatment, and before that I gave her my phone to put in her pocket because I had none, and I think at lunch time she went in the bathroom and read them all, and there was some messages about her, they weren't bad i PROMISE. I was just telling my other friend how she was hurting my feelings lately because she was being negative... She was really putting me down. I only said that. I didn't say " Oh I hate her, shes such a terrible friend " But now she won't talk to me, and her facebook status says " Oh thanks alot, your the greatest person .... " Help? :(