Vanity and pride are different things, though the words are often used synonymously. A person may be proud without being vain. Pride relates more to our opinion of ourselves; vanity, to what we would have others think of us. ↗
People who don't know me have opinions about me. That's the part that's very hurtful. Because how do you form an opinion about somebody if you've never met them or spent any time with them? So it's all based upon hearsay or things that they've read. ↗