My 92- year old step grandfather has become increasingly mean to my grandmother, who has literally spent the entire 25+ years of their marriage catering to his every need. He insists that she has been cheating on him and even has gone so far as to say that he saw her with the other man when she was on a trip with me and my mother. We have tried to speak to him about what he is doing, but all he will say is that "I know what I saw.". We want her to leave, but she thinks it is normal to be accused like this all the time. I am very worried for her, not the least reason of which is that he continues to drive! Any suggestions? I just want her to be safe and happy.