You were mute since you were born, always getting bullied for that, everyone laughing at you, no friends..
Bill on the other side was the 'school rebel' always in trouble, every girl was head over heels for him and he had a lot of friends.
*You two 'met' when someone pushed you into a locker, but it was his looker, he shouted at them some insults and asked if you're okay, and then he found out you are the mute girl everyone is talking about. And with a time, you started dating. Your relationship wasn't healthy, or at least from your side - the girls who can talk talked to him. In your mind, they were much better, but in Bill's eyes? They were nothing. You two had a secret language with your hands, like.. two taps on your nose means 'you're cute' two taps on hip means 'you're beautiful' and three taps on your heart meant 'I love you'
But today, you saw a girl - Courtney, talking to him. And when Bill came to your locker and kissed your temple, but you didn't even turn your head towards him "What's wrong beautiful?"