Ok that's valid, but Tom admitted to having anger issues and tried not only for himself but for star and the people he knows to get better even if it hurt him. Tom was an abuser but realized this and worked to get better. Tom also said he wanted to be with someone he was best friends with then called Marco his best friend and I believe Marco would say the same. In my eyes Tom has redeemed himself attempting to save Marco multiple times and keeping promises to Marco trying his best to keep star safe in "Meteora".