You're not supposed to sleep on ice - especially if it's drug-aided sleep, mostly b/c you could cold-burn your skin. If your nerves are affected you may not be able to adequately judge when "enough is enough" for your muscles, too.

That being said, I've done it numerous times [and I'm willing to bet others have, too. ;-)] with a barrier (like terry cloth) to protect my skin and using either actual ice or a medical ice pack which will melt or thaw quickly enough that the risk is lessened. I definitely wouldn't try it with a blue-ice pack or similar.

I usually do what you described for flare ups.

I think you should talk with your PT and chiro if your treatments are making you worse rather than better; maybe they need to re-evaluate their treatment plan for you?

I'm sorry you are having such a hard time right now. :-( Hang in there.