On this, I was bisexual through college and once I was married I am for the most part straight. (I say "for the most part" because gay and bi porn still is attractive to me. And yes, psychologically I can reassure myself that I'm not cheating on my wife with other women...but number 4 is still false.)
I will take exception to the wording on number 3 - understanding that these are myths about bisexuals, not truths - in that it isn't that Bis are "unable" to commit, it's that we're open to the relationships that both genders offer.
I've discussed this several times on
my blog, including
the most recent entry which is on the topic of group sex (in which bisexuality can play a very fun role).
I truly believe that sexuality, as with most things,
is on a sliding scale. Because I am happily married doesn't mean I am straight, however. I still have an attraction to men in the same sort of way I have an attraction to women. Whether it's something I act upon versus simply "have" is up to me as an individual, but being Bi is no more a choice for me than being gay or straight is for anyone else.
(I know gay men who love women's cleavage. I know straight guys who will admire, in private conversation, another man's shoulders or even ass. Women have more of a luxury to voice those thoughts, so it's less rare to hear an open a comment.)
And anyone who insists they've never had any kind of attraction for a person of the same sex is more rare than we think it is, based upon my observations. Doesn't mean they don't exist either, but finding people attractive and sexual doesn't mean anybody's going to act on it.