How many hours/days has it been since your last dose? Did you manage to taper down at all?
Honestly, whilst I fully appreciate the regimen that nznity described, I don't think you'll need to go to that extent at all. You should be fine after a few days cold-turkey, and just using some comfort meds.
The aches and the irritability are to be expected, BUT they should subside in a couple of days. If you can handle a few days of feeling icky, then just do that. Don't try to cover it up with other meds unnecessarily.
Tylenol AND ibuprofen taken together will help, as they potentiate each other, and caffeine will also help, as caffeine potentiates tylenol.
Do NOT increase your dose of lorazepam. That is going to be a waste of your script and honestly it won't be necessary.
Gabapentin is prescription-only in most countries so you would need to get it prescribed by a doctor. For your current situation, I would be highly surprised if any doctor would prescribe it to you. They will probably just tell you to go to bed for a couple of days and ride this out.
Let us know how you're going though. I think you should be fine in a few days