Noelle McCarthy: Twilight years are sucking me in

I no longer want to live. I'm dying already. You are too. Every breath we take brings us closer to it. With each moment that passes we're growing older, moving nearer to that moment of dissolution that waits for each of us, every one.

I am full of the heaviness of mortality this morning and it's all the fault of Bella Swan.

I spent the night with Bella last night. I did a Twilight marathon.

The new one is out, and so we went to see the whole saga to celebrate. All three of the films back to back.

Seven hours of courtly vampires and sexy werewolves, and forest fighting and immortal baseball, and silly dialogue and ridiculous abs.

And about three things I am absolutely positive. First, Edward is a vampire. Second, Bella wants to be one too. Third, I can see where she is coming from, sort of.

Bella, in case you have been curled up in the bole of a tree for the past five years, is the heroine of Twilight. A young girl whose defining characteristics are a serious lack of co-ordination, and a resolute determination to join the ranks of the Undead.

This is understandable, to an extent. Bella's boyfriend is a sparkly vampire called Edward who writes her songs on the piano and is sad because he can't read her mind. In this respect Edward is exactly like my first boyfriend, Stephen O'Leary, except Stephen didn't glitter like diamonds in the sunlight, or take me flying through the treetops of forests in the Pacific Northwest.

I don't doubt we'd still be together if he had. So there's Bella, and Edward, and they're in love, and they're trying to make it work, but it's tough.

Bella is a teenager growing up, and Edward is a 109-year-old vampire, who has been 17 "for a while". Aside from the age difference, and the thorny question of immortality, there are other complications, like an Army of Undead who want to kill them, and some camp Italians who want Bella turned into a vampire to serve their own ends.

There's also a rival for her heart - an eager young werewolf next door. You can see why this stuff is catnip to young girls, can't you? Besides the aforementioned clumsiness, and a penchant for falling in love outside her species, Bella has very little in the way of distinguishing features.

She is surly and morose, and has terrible dress sense, and yet, by the age of 17, there's a whole universe of supernatural beings willing to do anything to protect her.

When I was 17 I was learning about the Congress of Vienna, and writing letters for Amnesty International. The film-makers are mining a rich vein of wish fulfilment here.

At close of play last night, Bella was one wedding ceremony away from entirely renouncing her humanity in order to be with the man (or whatever) that she loves. Not just her humanity, though, her only chance at immortality in human terms - that is, the safety of her soul.

This latest film finds Bella desperate to become a vampire, but the previous instalment has also made it explicitly clear what Edward believes she will be giving up if she does.

He believes that vampires are monsters, creatures without souls, damned to perdition for eternity. Historically, this is accurate, and you can forgive him not wanting to inflict that on the woman he loves.

Of course, the fact that he is even capable of feeling this sort of selfless love for another being might be a good argument for Edward actually having a soul.

Certainly it's enough for Bella, who tosses hers at him as if it were a basketball. "Take my soul, have it, I don't want it," she tells him in what has to be the most terrifying line in the whole thing. Much has been made of the chaste relationship between Edward and Bella, his vampirism being an excellent objective correlative for desire, as well as an effective stop to it in this case, and so the love affair remains resolutely restrained.

Author Stephanie Meyer is from a Mormon background apparently, and while the whole thing reads as a fable about not having sex before marriage, I wish she had worried less about Bella's body, and more about her soul.

Bella Swan never talks about God; she never talks about anything really except vampires and werewolves. And there's a lot about this world that makes me think a magnet for vampires and werewolves is not the worst thing for a teenage girl to be.

But for an author and for film-makers to put Bella in that universe, with no sense of herself and no sense of her soul, is a criminal thing.

It's a huge disservice, not just to the character, but also to the story and to the legions of young girls who love Twilight around the world.