Funny how people react with hate whenever a character is cheating (whatever their reason might be).
It's like they're being the ones cheated on. Talk about being insecure.
Anyway, i liked this one.
What people probably failed to notice and the teacher pointed out is that when Ami invited Rei to the amusement park, three months prior, she was already in the process of breaking things off with all the other girls she was having a relationship with. The phone call was because she had contacted a girl, probably to break up and Rei mistook it as Ami two-timing.
The final trigger was probably Rei coming at her place when she was sick and Ami realized that Rei was there for her. So she decided to turn a new leaf. Unfortunately, communication failed.
Also, Ami is dropping out of school probably because her mother can't pay for it. She's basically abandoned. But people here are like "yeah, serves her right."
Thankfully, Rei isn't as heartless as you lot.