First,glad you and your son are o.k.Second,if you follow through with a lawsuit you better be prepared to possibly loose you driver,s licence.Once there lawyers dig into your past and health issues,they could very well yank your licence.I say your treading on thin ice,let it go.
My stepson has MS,was driving back from town,hit a deer,noone hurt,totaled the car,insurance cancelled,still has his license but can't get insurance. It really depends on how deep your pockets are. Petty is right,you may lose more than its worth.