"Some people will not hear you regardless of how much, how loud, how truthful, how loving or how profound you speak or write. Wish them well and let them go."
This is true. So many times have I seen people who would not understand me no matter how much I have tried to explain, no matter how many different examples I give, no matter how much love and care I did put into my words and gestures. And then, few months or a few years later, they would reappear and confess that my words were so truthful, but the refused to accept it then. Or they were not on the level high enough for (my) truth to come to them. "They were blind, but now they see".
Then I have learned to let them go. When the time comes, if it is important to their soul, they will find me again, or my words will come up from their memory. And I will be happy to touch their lives.
So if in the situation that you wish all the best to someone, but that person doesn't see the grand jewel you are offering, don't get angry or sad. Just let it go. And let it be.