J.R.
Ohhh, this is such a touchy subject. Just reading it makes me fired up about my own mil. lol Unfortunately, I don't have a lot of advice for you because my husband and I still go back and forth about the same sort of things as well. Recently though, he finally got the picture and said he will mention to his mother than she needs to be more careful with her words etc. It has taken us many arguments and discussions to get to this point. Just about every time she would say, or do something, I would make sure to mention it to him later or give him a look if he was there so he'd know I was upset. I don't know if my tactics are right or wrong but it's finally worked for us. I think that after mentioning so many things so many times, he was able to see that I was truly upset by her.
I had to remind him that our daughter's health, happiness, and well being is more important than anyone else's feelings. Hang in there and know you are definitely not the first one with these complaints!! :)