J.,
You pose a very difficult question here. Family dynamics are very sophisticated, and while the basic question may be the same to the many people who have responded here, the underlying causes vary vastly. There is little detail provided in your posting about your relationship with your mother, or with your spouse. Though I would tend to agree with the person who wrote, if you are inquiring here about other women in similar circumstances you are bothered, even if not by the fact that your mother and spouse are at odds. I consider that a good sign. In your mind, there is a question, and questions are at the heart of solutions to conflicts.
You do not get to choose who your mother likes and dislikes, regardless of how you perceive the person in question. To believe that you do, or to insist on hashing the issue with you mother is likely polarzing the conflict further, aside from it just being arrogant of each party involved to assume they know all the details that "should" be considered as valid that affect that choice, or any of the details that are, in fact, influencing it.
I suggest you read a couple of books. The first is Safe People, by Drs. Cloud and Townsend. I found it provided insights into myself that helped me to understand what part I play in the dynamics of my relationships, and what part I don't, and can't, play. The second is Taking the War out of our Words, by Sharon Ellison. This book provides a method for non-defensively communicating that has helped me get to the bottom of a great number of issues that effected my life, and probably wouldn't have, if I'd know how to keep the situation from polarizing. If you choose to continue to address your concern to your mother, the second book should help you pose questions and get answers that will help you reach the root cause, and the first should help you decide if you want, need or can affect a solution.
At the bottom of this, my instinct tells me to caution you about discounting any part of your family because they make a choice you don't agree with. We are social creatures. We Need our families; All of our families. Any situation that forces you to choose between one person in your family and another warrants a great deal of careful investigation and concern. Don't cut out your Heart to spite your face. Only God knows everything.