Physical & Emotional Abuse Support Group
Abuse is a general term for the treatment of someone that causes some kind of harm (to the abused person, to the abusers themselves, or to someone else) that is unlawful or wrongful. No one deserves abuse, period. Abuse can be emotional, physical, or sexual.

I'll be honest about it, it totally and royally ticks me off when people minimize abuse. For myself I know it's due in part to the abuse I endured that I have very high validation and justice needs in me, and because the lack of those things when I don't get them it feels like an attack on my autonomy, which I am fiercely protective of, so that's my baggage, but that kind of thing really ticks me off.
I think it's fine as paint that you both call her out on it, as long as you know the response will likely be more denial and minimization, and that can be another layer or trauma for some, so kind of evaluate that for yourselves, if you know what I mean.
You've got to protect what you value, it is never wrong to do so. If you value peace and tranquility put boundaries around your peace and tranquility and protect that, and it's nothing against your MIL, it's about protecting what you value. Good for YOU!
You are healing. It happens, WOOT! WOOT! You've been doing the work and you'll start feeling the benefits.