I hate my best friend now
Why do you hate your bestfriend? what did they do?
The reason is I think she's a traitor. She abandoned me in the heat of the battle!
Best friends are hard to come by. You should not hate your best friend especially it sounds like it's over something very small. I am sure there is a good reason why she abandoned you in the heat of the battle.
She left me in the middle of a war. She changed her religion, her ideology, even her sign in a year. When she lost the political race and became a minority, she betrayed the way she votes.
Sometimes war can change people. Instead of hating her why not talk to her and try to see her side of your story? Friends should be willing to hear what the other has to say before making assumptions about them.