Confused i like him and he likes me but he taken :(?

when we met he was single we didnt really talk until a few days ago..now all we be doing is talking we even stay up late everyday.he has a girlfriend but he did say he likes me.yesterday his girlfriend broke up but as a good friend i told him to tlak to her and try and work things out. they worked everything out but now he says he shouldnt have listened to me cause he knows he aint gonna be happy with her cuz he developin strong feeling for me.what should ido? i dont know what to tell him. i dont want him to leave his girl for me. if we gonna be together i want it to be the right way. no1 getting hurt. any advice