Nate: he was gone to much and you drifted apart he didn't want to but you said it had to be done for both of your sakes.
Sammy: he thought you cheated on him so he broke up with you.
Jack J: you hated how so many girls where constantly all over him and how he never told them to back off a little or not to constantly try kissing him, so you talked about it but that led to a fight and you broke up with him while storming out of your shared home.
Jack G:he did not pay attention to you he was either hanging out with the guys, working on music, or on his phone he just lost interest it seemed so you packed up all your stuff and broke up without telling Him why you just left.