If you rush things; if you make your lust for sex a thing that is to be feared, that is not controllable, your unicorns will flee from you. Be like the old bull, not like the Red Bull. Take your time. Build their trust. Walk down the hill slowly, and fuck them all.
Everyone's guilty of making assumptions at some time....judgement is human nature, it's a survival tactic...so you can't be too hard on people about it...just put them right when they make an assumption of you, if you care enough to...mostly I don't care enough about other people's opinions of me...the time I care is when I actually care about the person making the assumption.