Should I wait for a guy to "grow up"?

I've been best friends/ talking to this guy for going on five years now. We are very close and see each other almost every day. I'm in to fashion and hes always wanted a buisness so we just opened a boutique together last year. We are both only 23. The problem is he still wants to go out and live his life and talk to other girls because hes young and thats what his friends are doing. He says if he was to settle down right now he knows he would end up cheating and that would distroy everything for good. He tells me to do my own thing too for now and "in five years" hell be ready to settle down and get married. I know that he really isn't ready now, but I know we love each other still. Do i just completly say f*ck you and leave the store and move on completly or do I accept that hes young and let him get it out of his system so he dosn't cheat later on? When I say stick around I mean keep him as a friend and still work with him at the store..oh and he makes it impossible for me to be in a realtionship with anyone else as long as hes around..what do I do?!