Flash forward 15 years: Unfortunately, there’s a built-in sense of rivalry in every daughter-in-law/mother-in-law relationship. A woman and her mother-in-law are in a triangular relationship with the same man. The daughter-in-law’s gain is frequently the mother-in-law’s loss. And when another woman has caused you a loss, no matter how intellectually understandable it is, it’s hard to take. Try these ideas for solving this situation with your mother-in-law.