My Husban Is 85 Years Old We Have Been Marred

my husban is 85 years old we have been marred 1 year i know i didnt cheat on him but as soon as i found out he had the i went to my dr and had test done all my test came backnegative what could have caused him to get them and how can i keep from geting them from him no im not leting him toch me