Oh dear, this sounds a little too similar to our own mother. We've often thought, if anyone has DID in our family, too, it's her. She's in complete denial of her own traumas. She's never present. She parentified us, too. She told us all of our experiences were completely normal. Only during therapy did we gradually start to piece together, nope! Not at all normal experience. The thing is, our mother we learned, gaslights us. Like, a lot. We can't know for sure whether she has DID or not, but what we do know is she's toxic for not getting any help ever despite multiple interventions on her behaviors. It seems like to me, you're really wondering, is she a trauma surviver, too? Is it founded to feel hurt by this parent who may have been doing their best and may be like us? This is where logic comes in handy. Facts. Stick to the facts you know about how this person impacted your life and developement. Diagnosing her won't ease the discomfort and conflict of having a parent you love, because that's normal for a child to do and a parent who was harmful to yous, nonetheless. We've had to give up on understanding our mother. She doesn't change and I find that the only reliable thing about her. I'm very sorry you had a confusing parent too.