Soo sorry Pale Emperor you going thru this but I agree your wife & duaghter should be with you... Your wife might be encouraged by her family to leave you because they will tell her, she & ur duaghter are "in spiritual danger" & will miss out on "everlasting life", make sure you stay close to them, be very loving & do family things with them, show them ur still that wonderful husband & father & don't need to be in a cult to prove it...
About ur in law OMG i wouldn't allow her in ur home anymore, the nerve of her invading ur privacy, it sounds too me she was on a mission, she not only betrayed you but your wife's trust, totally disgusting! They have no boundaries & NO SHAME!!