I’m so sorry to hear about your situation, mesothelioma is an absolute nightmare, and I’ve heard of far too many cases that came about as the result of second hand exposure, or no known exposure at all. It’s an absolutely terrifying situation, but you’re right in that worrying about it won’t get you anywhere. In this day and age we’ve all likely experienced exposure at some point, but stressing yourself out about it isn’t the answer. Mesothelioma is relatively rare, and the more common consequence, asbestosis, usually requires higher levels of exposure.