I dunno Ach - I guess I'll be the odd voice out.
You gave up drinking and smoking for good reasons, yeah?
By taking up smoking again isn't that kind of like compromising with your AV - you're kinda here saying I can't face life without some kind of addiction, some kind of crutch - and that's just not true.
There is a lot of help around to help you cope - there's help here, there's help with your Dr and counsellor - maybe you need more help there?
I bet there other kinds of help at your school too.
It's up to you in the end, but if you're going to look for help to help you cope, isn't it better to look healthy life affirming help, not self destructive addictive help?
D