I think you manage by setting realistic boundaries and expectations. You want him out and away from you so that you can work on yourself and figure out which direction in life you want to go. You also want him to work on himself but you have absolutely no control over that at all. Keep in mind that no one changes in a week or two or even a month, taking him back right away based on words or some signs of change is usually our own desperate attempt at ending our own pain and fears and most often leads us right back to where we started.
Think realistically about the last time you separated and how quickly you rushed back and how much he changed, not much because look where you are today.