The teacher finally sent my best friend to find me
Why did your teacher need to find you?
I was missing from class and my best friend knew where I was.
It's good that your friend came to find you but you should be careful about getting lost at school.
My best friend is my partner and you are making out that he was nice for rescuing me. He's the one that left me after all.
I understand that you do not consider your friend nice if he left you alone. However, it's important that you do not go to areas of a school that you are not supposed to be in. You may get hurt and get in trouble by doing this.