I know what you're thinking. This chatroom is dumb. Why would anyone reveal the thing they're trying to hide? First of all, you're so afraid of it precisely because you know you can't hide it. Second of all, if you just reveal it here it'll be out there on your terms and you can stop worrying about it. This is a cleansing process.
And third of all, it probably doesn't matter at all. The Atlantic says we're capturing the most beautiful moments of our lives on social media, but we know better. What's that unflattering photo or unfortunate tweet (retweeted ad nauseum) that's always in the back of your mind? Let it all out or subtly allude to it below.