I totally sympathize with the thumb injury: I cut my thumb badly 4 years ago washing a coffee pot that broke in my hands. Only three stitches, but deep, and apparently damaged more than was originally thought because I still don't have all the feeling or motion or strength.
I developed new safety habits since then that have done me well:
1. No knives or blades to be left in soapy water. If you cannot see it, it can cut you.
2. No glass left in water at all, since you cannot always see it -- especially broken pieces at the bottom.
3. Don't go into the kitchen on a Friday the 13th. Yes, that was when it happened :(
However, the clutz gene is strong on my side of the family, and I have since then burned myself in some really stupid ways. As I refuse to give up cooking, my only new rule is to not let anyone else in the kitchen at the same time
. Which is something I wanted anyway!