Fellow black sheep here

I have a volatile mother. She has to control everything and while she accepts my diagnoses, she doesn't always believe that I am symptomatic when I am. When I'm depressed I'm lazy; when I'm manic I'm out of control. I have 3 other siblings (1 is my twin) and she adores them and showers them with affection. We've had problems outside of my bipolar too (when I was in PTSD crisis and learning to live with fibro), but it has almost entirely been bipolar-related in recent years. I actually think she loves me and the control freak in her just wants me to be normal and ok, but the way she deals with it is through screaming and name-calling.
The thing is, it's been going on for so long that I'm not searching for affection anymore, I'm just looking to end the screaming matches or periods of cold tension. So this is what my T told me a couple weeks ago: you can't change her. If you know that her behavior is unacceptable, tune her out. Send your mind to a "happy place." Don't let the situation escalate because there is no point. Keep in mind that you are doing this for yourself. Repeat to yourself, "I deserve to be respected." It will be very hard at first, but it should eventually become habit and you won't have the urge to engage in mind games.
We may never have the relationships that we want with our parents, so there's no point in continuing to feel miserable. Don't make it a life sentence.