I've OD'd about 10 times. A couple were on purpose, but mostly accidental. If I really think about it, I'm lucky to be alive. I had mentioned on another thread that I took 50 Ativan (anti anxiety med) in a space of 4 days. I'm only supposed to take 3 a day. There were 1 mg each though. So eh. However, my doctor kinda freaked out about it and said I could have killed myself. I'm going through a rough time atm, so not really sure if it was latent (just really want to off myself or just try to kill everything)
I have severe back problems from my old job and need back surgery so I take Percocet. I've hypothetically abused that before, just to numb myself so I don't have to deal with the way I'm feeling.
I told my shrink the other day, and my husband last weekend that I thought I was a drug addict. It felt really weird saying it. Mostly because I hate all recreational drugs (pot, coke, crack, meth etc) and I don't even drink alcohol. He thought maybe I was, so we decided to go to my shrink and ask her what she thought. I was totally honest and total her everything. Even about the Ativan. Surprisingly, she said she didn't think I was a drug addict and that I've just been triggered lately by my therapist retiring. So, I back on different meds yada yada, and I have to get my new anxiety meds (which is Xanax now) on a weekly basis so I don't OD.
So, to answer your question, I think most people, if not all, take drugs to kill and numb whatever pain they're going through. And, I've never been on coke, but if it's anything like mania it is the best fucking feeling in the world. I quite miss it actually, but I am quite the asshole when I'm high.
Oh, and I've used X (ectasy) once, and it was fabulous. However, I liked it too much and I knew that it would get me into trouble. I would have liked to try acid or shrooms but my head is so fucked to begin with, I think I'd have a real rotten time a regret it.
Best of luck with your kid though! I'm sure you'll both be fine. 