You can spend the entire day crafting the best possible explanation, finding the perfect string of words that respectfully takes into account both parties feelings, and it won't make a difference.
A normal, mature parent's response to your explanation may go something like this: "Oh my god, I had no idea I was making you feel this way. I'm so sorry and I understand why you won't take my calls anymore. I will do better from now on, and my line is always open if you ever change your mind!"
But you will never get that kind of response, not even close.
Instead, as she feels her proximity to you (i.e. control over you) start slipping, she will panic and begin utilizing manipulative tactics to bring you back into the fold. Guilt-tripping, gaslighting, bringing in 3rd parties (usually other relatives/family friends), and so on.
There will be no genuine respect for boundaries, no genuine understanding, and ultimately no genuine peace for you as long you attempt to hold low-contact with such toxic parents.
That's why the usual advice for dealing with such parents is no-contact. Except on this forum, that's for estranged parents. On here they would much rather see a victim continue dealing with a toxic parent, rather than doing the right thing for your health and well-being.
Good luck, but I see a long, turbulent path ahead of you as you attempt to navigate this unusual situation.
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