How do you make your soul-mate realise they should be with you if they're scared of getting hurt again?

the minute the person walked into my lesson i knw i was meant to be with them. i was scared of getting hurt though. the person admitted love for me but i brushed it off claiming they were just infatuated. they payed �50 for my christmas gift so i could go th them to america. the person as obviously hurt i wasnt allowing myself to be with them so i tried but asnt rady at that time so i ended it. hethen slept with somebody as payback. we started to get close again and he even save d my life but then i was reminded of his cheating and slept with somebody myself. we somehow got back together again after a lot of convincion my part but then after the rson went to scotland they had an epithany and spit with me. i am in love with the person and they are in love with me. we spent a lot of the holiday getting close. bu they are scared of being hurt again. how do i make the person see it wont be like that this time??