You're right, Daryl. It's the honesty and commitment that matters. The problem is that most of us don't find out we're married to a bisexual until years (sometimes decades) into our relationships. That is the thing that hurt me the most: the dishonesty. Though I didn't have the typical red flags (gay porn, secret sex toy stash, or illicit apps/messages), looking back I can see how the secret impacted my marriage. There was something I couldn't pinpoint...not exactly a wall...more like a thin film I could not penetrate.
I do think that some bisexuals are probably better suited for other bisexuals (though, statistically, most end up with opposite-sex partners). One thing I have noticed is that many describe their same-sex attraction as a "need" or an "uncontrollable urge" instead of a "want." I came across one guy in a forum who said he "felt like he was going to die if he didn't get to be with another man." I suspect that when the desire is affecting their mental health in that way, they're most likely GID.