If you do file suit, it will be a suit against her insurance company. Her insurance company will end up dropping her, but she needs to stop driving anyway. I agree about injuries bothering you when you get older. If you feel that the injuries were serious enough, go ahead and sue her insurance company for the bike and medical bills, it willl not hurt the elderly lady other than losing her driving ability, which could save someone else's life down the road. Just my 2 cents.