((((((catfish))))))
I suffer with this too, I am so sorry you are in pain. I had a good stretch where I was not picking/chewing also but then started up again when things got super stressful. I don't have any good advice about making it go away forever but in the past I found it helpful to get a bunch of leather or other thick type of fabric pieces and use a hot glue gun to put tons of little glue dots all over them. Then go about picking the glue off. It felt similar to picking my skin, especially with the leather so it would give my skin a break for awhile.
Oh yeah -- also I found crocheting to put me in a similar trance-like state as picking.... so it's a healthier way to numb out for awhile. It's just hard to get to yarn and crochet hook when you are trying to go about your day and do stuff. But, it helps with anxiety to get a chunk of time to do that. Do you have any hobby like that which is real repetitive that could be relaxing?