This is a post that needs to happen only because I see people using these terms in such different ways, I thought I should set down my own perspective on it all.
Sex drive/libido/arousal are the most straightforward of these. They’re more or less interchangeable to me. Libido is sex drive which creates arousal which is a thing your body does whether it’s convenient at the time or not. More a feeling than an emotion, if you will.
Sexual desire is where your own will comes in. It’s the cognitive part of feeling like acting on arousal and/or attraction and/or a conscious wanting-ness to have sex.
*Sexual attraction — ???
Really, how should I know?
But to elaborate a little more, sexual attraction is the specific experience of being drawn to a particular person in a way that you experience as sexual — a kind of gut feeling that someone is “hot” or “sexy”, or so I’m told. Sexual attraction is not the same thing (or is not always the same thing) as a willingness to have sex with someone. Important point here: people do not choose who they are sexually attracted to. It’s something you experience, like the weather, I guess. Wanting to act on it? See up there, sexual desire.
*Sexual attraction is the one that determines whether you’re asexual or not, because asexuality is a sexual orientation, and sexual orientation is about what people you have the potential to be sexually attracted to. Things like whether you have a libido, whether you like sex, and whether you’ve had sex before play no part in deciding this.
Sexual behavior is the action part. This is the category for “stuff you do”. This does not depend on or determine sexual orientation. We already know that a priest being celibate does not necessarily make that priest asexual. Choosing to opt out of sexual behavior does not eliminate sexual attraction (and the inverse is just as true: a lifelong lack of sexual attraction does not always go hand in hand with being forever celibate).
There are other forms of attraction, too, which I might talk about next time, but that ought to be enough for now. Here’s the important part:
These things do not always coincide. This is pretty obvious. We, as a culture, have already acknowledged this before — but once people get into an argument about the existence of aces, all of a sudden that all gets thrown out the window. And this isn’t even touching on the fact that romantic attraction without sexual attraction is a thing that can exist. Be we already know this. People have sex without being in love; people can be in love without having sex. People of all orientations sometimes choose to have sex with people they’re not very sexually attracted to, if at all. It’s possible to experience arousal even though you weren’t looking at or thinking of anybody who’s hot; that just happens. It’s even possible to be aroused and sexually attracted to someone nearby but not choose to have sex with them for whatever reason you darn well please because arousal is not desire is not consent.
If you already knew all this, then cool, you get to be happy that you’ve found someone who agrees. Or, if I’ve gotten something wrong here, set the record straight in the comments. Or maybe you just have more questions, which is cool too.