Benzos are meant to be prescribed to people in the OP's situation. He said he's not keeping up with work, not sleeping etc. He would absolutely benefit, in my view, from a small amount of benzos for use over a short period of time. You need to think about what sort of a person your doctor is, and about whether honesty or modified truth would best serve you.
My words of concern lay with the multiple statements the OP made about having had substance abuse issues with prescription drugs in the past and knowing that eventually he would end up abusing the benzodiazepines if he were prescribed them. Benzos on a 2-4 week course of treatment or utilized as PRN's are definitely useful, and it certainly sounds as though his situation is dire to the point where an acute form of intervention would be warranted. Given his admission of likely intent to abuse the medication, though, I can't suggest that he give them a shot without trying other routes (pharmaceutical and otherwise) first. Others' recommendations of GABAergic AED's like Lyrica (I would recommend trying Neurontin, first) or Atarax/Vistaril (anxiolytic antihistamine) make much more sense, especially if the anxiety is pervasive and likely to be long-term. It sounds as though this is the case, because the anxiety has wrought his life for long enough to cause extensive damage - we aren't talking about panic attacks that occur once or twice bi-weekly that prevent him from doing his homework that evening.
In any event, the underlying cause of the anxiety should be ascertained and addressed, above all. That process is likely to take time and should involve professional assistance, but in the meantime the OP could be helped immensely by some sort of anxiolytic intervention. I still believe benzodiazepines are not the answer in this particular case.
I want to give credit to Kipo for at least having the balls to ask for honest advice here, even if that meant admitting that he would most likely abuse benzo's if he were scripted them. Kipo, that kind of honesty is difficult to muster - especially when the benzo lure is right there and seems so appealing. As a member of this community with anxiety issues and who began benzo therapy close to your age, who now regrets that decision so thoroughly, I'm happy to offer you my suggestions - but I wouldn't be able to give you the best advice if I hadn't known you had a history of drug dependence. I
really think you ought to do yourself a tremendous favor and stay away from drugs that have a horrible dependence liability and withdrawal symptoms that can not only be deadly, but that can last for
years. I spent twelve months using diazepam with a doctor's help tapering down from over 5mg of Xanax/day, which is where years of using the medications got me, and ended up still having seizures when I got down to 5mg of diazepam daily. I had to quit the taper, and am still on the damn medication to this day - wondering seriously if I'll ever get to live life benzo-free.
Anyway, I can only speak for myself. I can only offer you what I believe to be the best advice. But damn if I do believe it, and none of our advice can substitute for that of a licensed doctor.
Good luck to you,
~ vaya