I do understand how the in-laws can get under your skin when it comes to the situation that you or anyone else is in right now. They don't understand MLC and they certainly don't want to think that their babies were the culprits. So, you've told her what was on your mind, now you'll need to find a way to zip it and not discuss your situation w/her any further. If she brings it up again, you can say nicely "mother in law, I would prefer to keep this matter between my h and me". Then change the subject to your toddler or the weather or something else.
Don't sell yourself short, this is a difficult path to follow and I think you are doing well. It takes time to climb that mountain and you'll get there. The holidays tend to be a bit rough, but they'll be over very soon and everything will be back to normal in the world once again.
Hang in there!
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
