Please explain to me the biual argument "Gender doesn't matter as long as you are emotionally attracted"?

I have heard this explanation many times and I gotta tell you, by a scientific standpoint it's a real head scratcher. I mean, it's good and all to say you pick partners based on compatibility and emotional attachment, but in my opinion ual urges would still be predominant. Whether you are straight or gay, everyone is ually attracted to a certain gender. People can't just ignore their ual urges because they are "emotionally attached" to someone they are not ually attached to. Can someone shed some light on this please. I'm afraid I'm getting a headache form this. LOL