I would say don't bother "coming out" unless it becomes a problem in your personal life: ie: causes you savere emotional distress. If you feel angsty becuase you are "lying to everone", the best thing
to do might be to tell someone you trust.
In day to day activities, I only mention my bisexuality to pepole I find singularly trustworthy or special or open
minded (or some combonation of the three.)
If you find yourself in love with another woman and decide to introduce her to your parents, it might be time to come out of the closet. If you fool around with another chick while drinking heavily, or to impress your boyfriend or something, no one expects you to "come out". In US culture, just about everyone does that kind of stuff, but no one talks about it (
). I am personly of the opinion that whom you fuck is ultimently only the business of whom you are fucking.
The focus should always be one your own mental health. If you are comfortable with it remaining personal, keep it so. If you feel like your "living a lie" unless you tell someone you should tell someone.
And finallly, If you don't think it's a big deal, don't let it be. You can mention it if you feel you should, and let others come up with thier own assuptions.