[quote="BobObob, post:14, topic:196286"]
As a student majoring in theology at a Catholic college that prides itself in orthodoxy, I don't see anything inherently wrong with dating someone who is attracted to both the same and opposite sex.
As a Catholic Studies major, I agree.
You must apply all the usual caveats, however: if this person is actively having sex with other people -- men or women -- or remains open to it, that makes him/her a fornicator, which is a deal-killer. If this person believes that attraction to or sexual relations with someone of the same sex is perfectly fine, that's heresy, which the two of you should talk about -- but, if he/she is insistent that he/she is right after talking it over, heresy should probably also be a deal-killer (just like insisting that birth control is okay). If he/she isn't Catholic, then he/she is not a heretic, but also doesn't have the Faith, which, in my book at least, is also a deal-killer.)
If this person is willing to spend the rest of his/her life having monogamous sexual relations with a member of the opposite sex, I say go for it.
So I guess there's no official teaching on bisexuality because it all neatly falls into established moral categories. Insofar as the bisexual acts promiscuously or homosexually, the Church condemns those acts. Insofar as the bisexual acts chastely and heterosexually, the Church is totally chill with that.