My friends bf's an *** but idk how to help...?

my friend kelsi has been dating this guy elliot for a while now, i think hes the biggest on the planet. hes got her crying everytime i c her. he practically d her on christm, we were at snowball dance,she wanted to go home and he refused to give her his phone(hers was dead), one of the girls had to when we found out, hes just an *** to her. a few days ago she broke up with him. he came to her crying to take him back and she did. Now she likes this other guy robbie. But hes going onto the service when he graduates. she doesnt know what to do cuz shes happy with both of them. shes scared to get close with robbie cuz he might go over seas. and shes sick of elliots ****. they are both wanting to fight over her but she dnt want elliot to get killed. i wuld love to help her but i dnt kno wat to do. wat wuld u do