A Libra parent's relationship with their offspring is often talked about and even envied. She is very warm and is capable of maintaining a close connection with their kids. While other parents have problems raising their children, the scale represented zodiac can just let things roll and have fun with it. That's actually one of their biggest secrets, they try to have as much fun with the kids as possible. They love and nurture their kids and they teach by example so their kids grow up to have strong values like they do.
Being like that, one would think there will be no problem with having them as a mother in law. Unfortunately, the love and affection is often limited to her own blood. They may give in to their children's whims and be strict at the same time but they do try not to be over protective and give them as much freedom as they think is fair. When their children gets married, though, they can't help but be meddlesome in a way that they have never been before. Generally, Libras like being the center of attention. So when their child, especially a son, gets married, they can't help to be catty and criticize the way their (son or) daughter in law does the things that they used to do. From the food you cook to the way you clean the house or the clothes that you wear, they will find something to comment on. The Libra mother in law won't say it in a tactless way, she will put it in a matter of fact and distant way which can be cold for you, as warm as her personality is.
Don't get heart broken, though. It won't always be that way. Things will turn up but you need to work on it too. The best way to start is to ask her questions. You can try to be the perfect wife but let her realize you're not competing with her. Instead, seek her advice on things. If you're cooking the husband's favorite dish for the first time ask her how her approach would be on it. How he wants it exactly. She will feel superior to you but also approve of your willingness to please the child she raised. Make her feel she's important. The last thing a Libra mother wants to feel is that she's redundant and that her child doesn't need her anymore. There is no question as far as her grandchildren are concerned. She would want to be a part of it so encourage them to be close to her.
Libras believe in the sanctity of marriage and they won't purposely jeopardize your relationship with their child. She will just seem interfering because she wants things done the way she's used to. Again, she wants to feel she still matters in her child's life. Don't be scared to make a connection with her, the least she can give you is acceptance and fair judgement and even that is a lot coming from an in law.