Suggest Treatment For Sickness And Weight Loss With History Of Bulimia Nervosa

I had bulima about three years ago. Recently I have started to get sick again. I have lost about 10 pounds in the last four to five months. However, getting sick now is not very often. How can I stop this before it takes hold again, but continue to loose weight. I am 23, 5 9 and about 124 pounds.