I Have Been Suffering With Some Type Of Skin Rash, Acne & Blothyness. How To Deal With These Symptoms ?

Ithchy> Blotchy > Bumps > Whiteheads... cant break this depressing cycle. Hi, I am 19 yrs old female and I have been suffering with some type of skin rash, acne , blothyness. Im really unsure of what it is. Everytime i try to change my diet and the way i eat, this happens to me. Started occuring from 2008. Unfortunately i am a yo-yo dieting type and like to try out new diets. Everytime i change the way i eat, 4-5 days or a week in it appears on my chest. I feel a tingly itchy sensation in the center of my chest between my breasts... than i know its coming. The only way i know how to counteract it is immediately stopping my diet and workout regimen and going back to being sedentary and eating whatever i want. The first time dealing with this I wanted to lose weight for an upcoming wedding so i didnt let it stand in the way. This left my face badly scarred all over. I continued on and I continued to break out on my chest, face (chin, and T-zone. The blothcy skin goes from blothchy under the skin and slowing rises to the surface, after a few days becomes raised-ish bumps very slightly and spread to the inside parts of my breasts. Later they form into white-head type pimples . My face itches and feels allergic almost and dry with blothchyness 2 days before the actual white heads begin to form. On my chin and between my eyebrows the whiteheads form 3 or 4 at a time and if i dont pop them they all form into one big one. First time back in 08 i didnt pop them and it eventually left my face completely scarred. I thought it was a food allergy to excessive amount of milk i was drinking the first time I went on a diet. That proved to not be the problem when i did a detox cleanse (master cleanse) for 9 days where I drank nothing but lemonade made with water, lemon juice, organic syrup, and cayenne pepper. I have just been telling myself its my body s way of detoxing and getting rid of all the toxins i have. With intense workouts i break out so i figured its the fat burning and trying to sweat out through my pores. This time around I m doing Atkins and I was almost certain i would have no run ins with my \