Coffee, stims and cigarettes were my demons, too (the whole teenage girl fat obsession thing). I spent most of high school on whatever I could lay my hands on, from OTC Dexadrine to Black Beauties. In my 20s it was Jolt Cola and Diet Pep before they took out the ephedrine. And then in my early 30s everything went to hell, virtually overnight, weight went out of control, skin went to shit, developed killer insomnia, constant exhaustion, body aches, became allergic to EVERYTHING chemical. It's taken me 10+ years to get my system back to some degree of normalcy.
You'll burn out your adrenals if you don't start being kinder to your body and start relying on healthy nutrition and actually being rested to feel functional. When your adrenals go haywire, weird health problems start cropping up.