please advise

the husband loves his wife alot he says he wants them both and he has just fallen in love with that girl as they were working together and it had nothing to do with the wife wether she was good to him or not and he wasnt looking for someoneelse it just happened he says sex has nothing to do with it he just fell in love with her he has never touched her they talked only on the phone. The wife has told him that he is living in fantasy and she will kick him out of his life if he would go ahead with this marriage and this is so weird he wants them both to live together with him or get a separate house for her and give them equal rights as stated in islaam, he also says to his wife she would earn a good deed if she lets him go ahead with this because the other woman is a sikh and is ready to convert tro islaam.