I remember a time when I thought that what you thought about me was VERY importent. In fact, it was life or death. I spent every moment checking on you, making you laugh, wondering what you thought about what I just said or did, and if I thought you liked it, I was excited, but if I thought you didn't, I felt depressed.
One day, when I sat still for long enough (I'm rather a slow learner), I realised that you don't exist, at least not in the way I thought. I also figured out that I can never know what you think, and I don't so much care anymore either.
Amazingly, when I stopped caring what you thought, I was free to care about you. And when I realised that I can never know your inner world, I turned my interest to mine.
And this is what led me to the happiness I thought I wanted YOU to provide. Delightful.