Welcome to Just Answer and thanks for your question. Not to be trivial, but your best option may be handcuffs. As long as you continue to pick at any lesion, it will not heal well. Perhaps if you covered it with a Bandaid at all times you aren't bathing, you could leave it alone for 2-3 weeks so that it has a chance to heal on its own. The constant picking at it runs the risk of infection and scarring, and, of course, won't let it heal.
The best options for treatment are an antibacterial cream (Neosporin is fine). Oral antibiotics (like doxycycline) more to prevent infection than anything else and Tylenol by mouth for pain should do fine. You can try warm compresses when you are bathing it. Then antibacterial cream and a bandaid. Particularly since you are prone to picking at scabs, it is best to keep it covered 24/7.