Is it necessary to come out if you're more likely hetero-romantic and bi-sexual?

I picture my orientation as something like this:

Emotional attraction (As in crushes, etc.)
|---X---------------I--------------------|
Straight_______Bi_____________Gay


Physical/sexual attraction
|----------X*------I----------------X*----|
Straight_______Bi______________Gay


One can draw the conclusion that I'm bisexual and heteroromantic, right? (Feel free to suggest otherwise!)
So since I apparently seem to be more likely to have a boyfriend rather than a girlfriend, do you think it's necessary to come out to people, especially since they normally don't even have anything to do with who I have sex with?

(*It pends more or less between those two spots, usually more on the right side of the scale.)

 

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