Adultery

Hi sir I wanted to know that one of my close friend was having an affair in the past with whom she was physically involved and before marriage she told everything to her husband also but after marriage her husband behaviour was too rude with her ..he even use to beat her on small stuffs so she started talking to her ex which was not on a regular basis..she use to talk him in a month or between 2 to 3 month intervals .during the chat they shared there past lives but discuss many things but she has never share any nudes or bad things with him but her ex was of overfriedly nature so in joke he use to say her many things like janeman and all ..her husband has downloaded a spy app in her mobile with which he came to know about all and also have some of their call recordings but after marriage she never met her ex...her husband also got evidence of her past physical relations with him and present chats and recordings though she never met her ex after marriage..now her husband has filed divorce on basis of adultety on her.what can she do now as after marriage she never even met that guy??