You can't change someone's personality
I have a fairly good relationship with my mother-in-law. We can chat easily, and I know she appreciates how I’ve supported her son over the years. But there’s a problem. When I ask a question about one of her friends or another family member—like “How was so-and-so’s baby shower?” or “What is ‘Shelly’ up to these days?” —her first comment is almost always derogatory gossip. She’ll have negative comments about her daughters-in-law or mention her niece is being a “diva” in wedding planning. After visiting a first-time mother, she told me the woman’s house was messy and that she had no right to complain about how hard it was because her husband was helpful. (My MIL had to do almost all of the childrearing by herself.) I usually just say, “Oh,” or a neutral comment that disagrees. But of course, I wonder: What does she say about me when I’m not around? My husband agrees and does not admire this quality in his mother.
How best to proceed? Should one of us bring his mom’s attention to this habit? Or have a comment at the ready to stop the gossip in its tracks?
— Loose Lips Sink Relationships
Re: You can't change someone's personality
Unfortunately, that's who the MIL is. She's a gossiper and critical of other people. And, of course, she negatively gossips about the LW also. If I were the LW, I'd just take it with a grain of salt since she does seem to like me.
And definitely don't divulge any info to her that the LW and their H wouldn't want others to know.
Girl, don't tell your MIL anything you don't want literally everyone she knows to know about you. Dont engage in the gossip. She's not going to change and your relationship will likely never be deeper.
Don't share anything personal with her and stop asking about other people. If she starts with the gossip, change the subject and don't feed into it.
mood, so I also know what to protect. It sucks, but it is what it is.