You'll stop caring what other people think about you, when you have something more important to care about. If you care too much about what other people think it's probably because you don't have something more important to care about.
When you have something worth being embarrassed about, when you have something worth being belittled about, when you have something worth being ridiculed for, when you believe in something so intensely that it's so important that you're willing to lose friends or the respect and social validation that's when you stop caring what other people think.
And the irony of this of course is that it is the moment everybody starts respecting you.