My bf is leaving for Kuwait how do i earn his trust back before he leaves in a month?

I love this guy and i ****** up !! i told him i would never talk to my ex who is also leaveing they have to go together but anyways i did and the first time he for gave me well i need a ride to school and my mother couldnt take me neather could her bf so my mother called my ex cause he still friends with the family but me and asked him if he would take me . well i didnt say no and my bf found out and fliped and broke up with me . i love him so much and he said that if i ever want to be with him again i have to earn his trust back. hes leaveing in a month and i want to be with him. i have cried to him asking him to take me back i went to his work and asked for him back. im so worried about him leaveing and not coming home . how do i earn his trust back?????????