Whether or not Sandusky's wife believed it is another story entirely. No doubt there have been testimonials that states that Sandusky's wife knew that her husband brought home young men into their home and even have them spend the night. She most likely knew that the abuse was occurring but nevertheless refused to believe it.
If something like that was going on for that long, how could she not at least suspect something? And when you live with someone for that long, you KNOW when there's something going on. That said, I think she went into denial the first time it hit her how depraved and disgusting he truly was. Who would want to believe something like that about someone you love and spent your whole adult life with?
Yes, I believe Jerry Sandusky's wife must have known about the abuse he was committing to young boys. How could she have not known? And, given that this abuse lasted for quite a long time, I do not see how she could not have picked up on some sort of pattern.
None of Jerry Sandusky's victims in either Grand Jury or actual trial testimony put Sandusky's wife (Dottie) at the location of any of the assaults or having any complicity in the actual child abuse. Men keep secrets from their wives all the time, this appears to be one of those cases.