As per your introductory posts on the New Members Introduction forum here,
http://neurotalk.psychcentral.com/thread177992.html

Many of your symptoms, sensory, memory issues, can be traced to your RX drug use of simvastatin and gabapentin.

I won't repeat the content of that post here.

But I will say this. Metformin often lowers cholesterol by itself by changing your metabolic profile. Consumption of fructose and sugar, and/or alcohol will cloud this benefit substantially.
So consider this, if you decide to discontinue your statin.
You will have to discuss this with your doctor, if you decide to discontinue the statin.

But metformin has a negative impact on B12, and that will create other nerve problems with time.

Also I'd look at your lifestyle, and exposure to things in your environment. Sometimes soaps, solvents, cleaners, chlorine, gardening chemicals will affect the nerves in the hands.