Did you advertise your sexuality with the world before you knew you weren't vanilla? By that I mean, did you tell your friends or family every time you got laid? Or looked at some picture you found erotic? Or when you masturbate? (Yes, there may be a confidante (sic) with whom you share secrets, but I'm talking about how you lived in the vanilla world when you were vanilla.)

So why do you think you need to advertise that you prefer sex that currently doesn't fall within the bell curve? Of course you want to keep it somewhat secret, away from those who you think would disapprove... but that's no different, per se, than not telling your father when you first lost your virginity. So why the guilt over keeping your private life private? Because others might disapprove "if they knew"? Well, many would disapprove if they knew you have/had premarital sex. Many would disapprove if they knew you enjoyed oral sex, (still illegal in some states.)

How much do you unequivably know about the sex lives of those in the vanilla world you worry about? Have they specifically shared with you their utterly vanilla sexuality with you? Or are they, unknown to you, also a bit kinky? But wait... that's private. So maybe it's actually NORMAL to have multiple facets to your life, that don't "publically" mesh and therefore... no, there's no reason to feel guilty.