First and foremost, I believe in communication. I totally disagree with any assertion that silence between spouses is better than talking. So you spoke up to the wife. What's she going to do, divorce you? she's doing that anyway. Good. State your case, be a man. Sounds like you were fair and logical in the discussion. I think you did a great job with it. Keep it up. Stand your ground. Don't let her walk all over you. It won't make her like you better. Silence won't make her turn around and say she loves you. Silence will only convince her that she can do what she wants, you are afraid to object.
As for MIL. I'd like to see your response be more specific about where she has crossed boundaries. You talk about her toxic attitude. i have no doubt this is something she is quite proud of. So simply naming it, won't make her see what is wrong with it. I think you have to show her specifically what it is she is doing and how it affects the boys.
