Hand/fingers red and leathery

It started with the cuticle of my right thumb, and somehow worked its way around to the back of my thumb and down all the way to the bottom of my palm. It's a problem for all my fingers, by the thumb is the worst. All my finger tips are swollen and red, but my thumb... oh god, my thumb. Red. Bright bright glowing red, all the time. LEATHERY. 4 years of this and my thumb/palm is like an inch thicker than it should be and feels like leather. Which makes it easier to pick at, because I don't feel any pain... all the nerves are gone. Trying SO HARD to stop. Feels impossible. I use nail clippers and just peel the skin away until it bleeds. And it takes a long time for it to bleed. Many layers of scar tissue. I look down and there are PILES of skin on the desk below me. I sweep it into the trash can. I continue. It's been a few days now and I've been amazingly good. Haven't picked. But, god, I am aching to....... I can't see this as the end of it. I feel like a relapse is inevitable. And it will feel SO good.. followed by horrible regret.