Welcome to SR!
I would recommend you read the stickies at the top and read many of the posts around here. There is alot of good knowledge here!
My AH was also abusing pills and he did the taper off method. He was taking a few a day like your AW, but he was buying them off the streets. When he began it was really hard. He was running to the bathroom, couldn't eat, couldn't sleep, was irratable and was sweating alot. It helped him to drinks lots of fluid, stay busy and to work out. If she can get the doctors help with getting off of them then that would be the best way. From my experience what ever amount you think she is taking . . it is normally more. Addicts in active addiction lie, lie and then lie some more.
Is this your AW's first time trying to quit? If she attending NA?
What are you doing for yourself? Are you taking care of yourself in this process? Are you attending Nar anon or Al anon meetings?