Exercise, Cleansing Diet and hydration will do it's job of eliminating trace toxins from your body, thus eliminating the physical urge. The mental addiction is different depending on how long you were using. Some drugs re wire the brain to believe that this chemical is as needed as food or water. Meditation and self reflection are known to allow the brain time to repair this imbalance to its more genetic wiring.
Diet- Lots of greens, beets and colorful fruits and veggies to help your body push the toxin out. LOTS of water. I would suggest a Juice cleanse for a few days but that's just my opinion.
Exercise- Since your goal isn't just to be better at Parkour or to Gain Mass I would suggest a high intensity (High Heart rate and sweat that hit multiple muscle groups) Workouts (Insanity, Spartan, Spin). However, most drugs cause a lot of cardiovascular stress [tearing] so you should hit it hard but be very mindful of your heartrate for the next year or so. 120-130 is average active hr. if you get higher take a few breaths and if you feel sick or light headed slow down.
Parkour- Don't go out and do Big Drops or huge gaps. Work on precissions, small Jumps, Vaults and climbing.
Parks are great for Parkour. see what I did there?
You don't really "Need anyone" else to train you, just go out and jump onto and off of curbs and picnic tables, then over stuff.
Be safe and Have fun, brother. I would say good luck but you don't need luck you got this