Luke ~ someone who isn't famous. You break up due to distant however you both agree to this. But when you see him with his new girl all the old memories come flooding back.

Ashton~ Hasley. You break because you felt like you never saw him. You tried to make it work but you weren't happy so you both moved on. However, he moved on faster when he found Hasley

Calum~ Rena from Hey Violet. He actually cheated on you with her. (I'm so sorry this one is sad af) they were on tour together all the time and Calum told you in was "one drunk night" but ended it with him and now they are dating.

Michael~ Meghan trainor. They met at a jingle ball concert after you broke up due to hate by the fans. Since Meghan was another celebrity there was less hate and they started dating.