No need? I disagree, just based on my experiences of raising my children who have a mentally unwell absentee mother. I also disagree it's manipulation, as that implies lying to them to achieve a selfish goal of your own, whereas a white lie is intended to be for their benefit.
My younger children still need to hear from time to time that she loves them, even if the obvious reality (to me, and my older children) is that her behaviour demonstrates quite clearly that she doesn't.
But, to ease their young minds, and help them sleep when the doubts come, I tell them that she does love them, and always will so, but she's working on some challenges that make it hard for her to tell them in person.
To quote Thackeray's Vanity Fair - "Mother is the name for God in the lips and hearts of little children."
(She has supervised access, but won't use it because "she did nothing wrong", and using it appears to her, as an implicit acknowledgement that she did something wrong)
I dislike lying to them, and I'll admit I feel angry when I do so - they love her because she's Mom, but she doesn't deserve their love - but it safeguards their mental wellbeing until they're old enough to face the unvarnished truth.
I also think of the day my father died, twelve days before I was born. He died smiling (I'm told) despite the intense pain, because of a white lie.
He was dying of cancer, and they desperately trying to induce me so he could meet me before he died, but no dice. And they'd been unable to discern my gender via ultrasound. He was desperate to have a son. (this was the 80s, so you know, patriarchy was the norm, etc. etc.)
In his last hour, he asked the nurse if his child had been born, and she lied magnificently - yes, you have a beautiful baby boy, he's eight pounds five, congratulations. (Which was not a bad guess, I was eight pounds 10).
While they're wildly disparate circumstances, they share a commonality - the unvarnished truth isn't always the best option in some circumstances.