Try not to stress out too much about this, my friend. If this person is not connected to your main social circle of friends, then I wouldn't worry overly much, as I doubt he will show up at your door with a lynch mob in tow. If he is connected to one or more members of your close inner circle, then it may help to go to the ones you trust the most, and who respect and care about you the most (as I'm sure all of them do), and attempt to do some damage control by telling them the mistake you made. If they do indeed care about you and respect you, the revelation of your 'secret' is not overly likely to make them just forget the good person they know you to be.
Also, please keep this in mind, as it's important to consider: when something like this goes down, you will sometimes be surprised at the allies you will find amongst those you know. Despite what the media makes us think, the entire world is not against us, even though it often seems that way due to the fearful and deafening silence of all the fence-sitters and genuinely open-minded people out there.
We all make mistakes, and believe me, this one will blow over in time. If you need us, we are always here for you. If you ever need to talk to me outside of the board, please feel free to e-mail me at: dissident57[AT]fastmail[DOT]fm