If it is something that really REALLY worries you buy a steel boat.
The path to "earth" is not interrupted by fibreglass so hull damage is most unlikely. If in side when you are hit you are in what is called a Faraday Cage and if you have to be struck then that is a good place to be. [ You might be deaf for a day or two - ask me how I know this.]
But there is problem that only steel boat boats may suffer from subsequent to a strike, the hull can become a strong magnet and your compasses are useless. Mine pointed to 137 degrees regardless of my actual heading.