Her or her

Story starting

Hey I'm Betsy(random name huh) and this is my journal were I keeps secrets in. Well today was probably the best day of my life because I get a best friend and a enemy
(Not good) But I have a very annoying teacher for our group who also happens to be my... Step mum. Not very funny I thought. Having your mum at school... sorry STEP mum.

Hey Betsy said my best friend Bayley. Oh hi Bayley wanna come for a play at my house in the weekend. Sorry Betsy but I'm going to someone else's house...
Who's I asked? She paused and said Judys. She said. I was stunned, I was thinking about inviting Amber over for a play but didn't because of Bayley. But now that I thought about it, I will invite her over since Bayley has invited Judy over. The bell rang and I was thankful