What else can you do?

I’m wondering about this “new” theory that is life-changing—the two little words that people can’t stop talking about that Mel Robbins is probably going to make millions on.
Full disclosure: I haven’t read the book, so I’m not a reliable source. I’ve only read about the book, and those reports were pretty clearly at maybe a fifth-grade level.
You know what I’m talking about, I’m sure: Let Them. The theory that “will forever change the way you think about relationships, control, and personal power.” Or, you could essentially learn the Serenity Prayer and apply it to your everyday life.
In my day it was “Don’t Let the Bastards Grind You Down.”
Hundreds, maybe thousands of self-help books have broached the subject of living your best life by not allowing others to occupy your thoughts. You’d think we would have it by now. So why don’t we? Maybe because we’re social creatures and we need other people. And that need translates to caring what they think about us. Duh. Can we fight against that? Of course. Will we win? The jury is still out.
Toxic people have been identified as bad for us, and we’ve been warned to weed them out and not allow their energy to defeat us. Check. Narcissists are to be avoided at all costs. Check. Friends who criticize rather than propping us up are not really friends. Check. And on and on—ever since someone saw a way to make money by selling us on the next best idea to change your life for the better.
There’s nothing wrong with the book or the ideas in the book—in fact it’s all good advice that’s been re-marketed into a catchy two-word philosophy. Is it “ancient wisdom”? Perhaps. I bet some Tibetan monk had it nailed centuries ago. Is it science-backed? It is if it helps people. How can it be a bad thing? It can’t, not really. It’s just that Let Them is so obviously simplistic.
If you believe that you actually have no control over the actions of others, then you’re already most of the way there. I’m going to suggest that sometimes you can influence the behavior of others, especially the “others” who admire you or who believe you to be wise or at least to care about them. And vise versa. People you care about can influence your behaviour, too. Maybe that’s why people feel the need to buy a book written by a person with such impressive credentials. So she can influence your behavior? Do I sense some irony, here.
If you don’t embrace Let Them, does that mean you’re liable to slide back into caring what others think of you? Will you still compare yourself and find yourself wanting and/or happy to be better off? Probably. We have to fight that impulse every day. Because of that whole social animal thing we have. Remember no man is an island? The sum of the parts? Problems solved is a problem shared? Teamwork saves the day? Shall I go on? Okay, not.
People matter to us. Watch any person separated from their people. They will look and look, expressionless. Then they see their person. Big smile. Relief is visible. Hugs, laughter. Connections comfort us. Those same connections complicate our lives and cause certain people to write books helping us to not get sucked into unhealthy connections. I don’t wish anyone ill will; certainly not a writer. Writing is hard work, darn it. Taking a simple concept—love yourself—and stretching it out over x number of words on x number of pages (I told you I hadn’t read it) might be hard, too.
After all, I spent over 600 words pondering that simple concept.
I’d love to hear your take. I’ll even Let You.