my humble opinion is that Maam ur husband doesnt need any medicine, he needs a reality check. Why dont u tell him about ur affair and how u have forgotten that so u can be loyal to ur husband, even if u dont have one make one up, and tell him that if u being a woman can do that why cant he do it being a man. If he was so much head over heals for that woman he should have gone against the tide and married that girl. Whats the point of grieving and sighing when he couldnt be the man when it was the time. And now not only is he ruining his own life but he is going to ruin urs and ur kids. May Allah be with u!