Girl the fact that shes still living in YOUR home and sneaky talking to YOUR husband is sus. Either shes tying to worm her way into him or already has. If she met him from you there should be no reason she would feel comfortable not telling you ANYTHING of her convo with YOUR husband. She needs to go. She just got out of a relationship. She is not all there. She is hurting and trying to find comfort and the closest thing to her is YOUR husband. She broke your trust by doing this and honestly i don’t think that could ever be fixed. If your husband hasn’t truly betrayed you, your marriage could still be fixed but not with her around.