HELP!!! demodex problem complicated by existing conditions

Hello everyone. This is my 1st post but Ive spent much time here in the past few months looking for answers. I suppose that as we all struggle with looking for a cure for this nasty and debilitating infestation, Ive discovered theres not a one size fits all solution.
Ive had this whole body demodex infestation for a few months now, at first thinking the bites and sores I was receiving were from a massive cat flea infestation we were dealing with when in fact the fleas had long gone weeks before and my dog and dh were fine. I also had a severe allergy to the fleas which didn't help!
My main problems are that Im on many different meds for bipolar as well as Fibromyalgia, so am fearful of ingesting anything which may interfere with they're effectiveness. Im also hyper-sensitive to drugs and have had many bad reactions in the past. What to do?!?!
Also because of the Fibro, I am unable to shower/bathe daily as it often brings on a flare-up of symptoms, which in turn stresses me and then seems to set off the mites further.
So far I've used DE both internally as bedtime drink and also on my sheets at night, which dries the nasty things out and means I get some respite from the itching and crawling. That and lots of Benadryl!!
Also I find that when I feel a group of them and I itch my skin, even gently, that my skin seems paper thin and I end up with a wound which takes weeks to heal as they seem to feed on the scab that forms.
All of this is turning me into a nervous wreck. No matter if Ive tried tea tree or neem, borax or peroxide, nothing is enough or works. Im lost and depressed and at my wits end. And im not physically or mentally strong enough to do what is required to rid me of these parasites!!
Can anyone suggest a physically easy protocol I can follow that will rid me of them? Or what I could say to a Dr that would convince them to give me some effective medication? Any help you can offer Id be very grateful to hear from you. Sorry for long post!! Best wishes & health to a