Before we get too heavily into psychoanalyzing Susan (from a distance), it might be helpful to remember that she's a
fictional character, and that there's no "real" Susan to feel sorry for because there's no real Susan.
That being said, the
character of Susan is not without meaning, because Lewis imbued all his major characters with meaning, and especially since 1) this was his last Narnia book, and 2) Susan's absence was such a discordant note in the general joy of the New Narnia. Lewis was using it to make an instructive point, and when a genius like Lewis does that, it's a good idea to attend to the instruction. Here's the actual dialogue from
The Last Battle:
"My sister Susan," answered Peter shortly and gravely, "is no longer a friend of Narnia."
"Yes," said Eustace, "and whenever you've tried to get her to come and talk about Narnia or do anything about Narnia, she says 'What wonderful memories you have! Fancy your still thinking about all those funny games we used to play when we were children!'"
"Oh, Susan!" said Jill. "She's interested in nothing nowadays except nylons and lipstick and invitations. She always was a jolly sight too keen on being grown-up."
"Grown-up, indeed," said the Lady Polly. "I wish she would grow up. She wasted all her school time wanting to be the age she is now, and she'll waste the rest of her life trying to stay that age. Her whole idea is to race on to the silliest time of one's life as quick as she can and then stop there as long as she can."
"Well, let's don't talk about that now," said Peter...
Now, before anyone drags in the old canard about Lewis being anti-women, attend to this quote from
Magician's Nephew:
[Uncle Andrew] put on a very high, shiny, stiff collar...He put on a white waistcoat with a pattern on it and arranged his gold watch chain across the front...He put on his best frock-coat...He got out his best tall hat...he took [a flower] and put it in his button-hole..
Children have one kind of silliness, as you know, and grown-ups have another kind. At this moment Uncle Andrew was beginning to be silly in a grown-up way. Now that the Witch was no longer in the same room with him he was quickly forgetting how she had frightened him and thinking more and more of her wondrful beauty...
"Andrew, my boy," he said to himself as he looked in the glass, "you're a devilishly well-preserved fellow for your age. A distinguised looking man, sir."
You see, the foolish old man was actually beginning to imagine the Witch would fall in love with him. The two drinks probably had something to do with it; and so had his best clothes. But he was, in any case, as vain as a peacock; that was why he had become a Magician.
There are many other examples of this in Lewis' writing, particularly in
The Great Divorce (chapters 5 and 9 in particular), the fussy self-importance of Curry in
That Hideous Strength, and in the short story
The Shoddy Lands, found in the collection
The Dark Tower. The pivotal point is that we humans have a tendency to let the trivial things of life occlude our view of the greater things. Vanity is one example of this, as both Uncle Andrew and Susan demonstrate. Lewis, speaking through Lady Polly, makes clear his opinion of this folly: "I wish she
would grow up!" He sees these "adult mannerisms" for what they are: shows and posturing. To Lewis, being "grown up" meant much more than clothes and cigars (or nylons): it meant being a person of your word, having courage and fortitude, and keeping the important things clearly in sight. Susan's tragedy wasn't that she traded in Narnia, but what she traded it in
for. Imagine how different the dialog would have been if Susan had chosen a more mature path; say, honorable marriage and motherhood, or charitable work, or even just being a working woman who looked after her duties to parents and others. The tragedy of Susan isn't that she didn't make it into the New Narnia (Lewis deliberately left that door open), or that she lost her parents and siblings, but that she traded her Queenship for a mess of pottage.
To me, speculating that Susan was somehow "hurt" that she wasn't allowed to return to Narnia, and out of this hurt rose her rejection of Narnia (thus, conveniently, casting some of the blame on that Big, Bad Aslan) is simply nonsense. Susan was already pulling away from Narnia even in
Prince Caspian. What did Aslan say to her when they finally met at the base of Aslan's How? "You have listened to your fears, child." Susan was already giving in to fear, and what little we know of her later life indicates that she followed through on that path. Women who "race on to the silliest time of one's life as quick as she can and then stop there as long as she can" are women who fear (I know a few): they fear the creeping advance of the years, the loss of the bloom of youth (so worshipped by this culture), the decline in attention. Men suffer from this, too, it just manifests somewhat differently ("Mid-life crisis"?) Unlike Lady Polly, who gracefully welcomed the gift of age and maturity, Susan (from what we know) fled from it by setting up a false sanctuary (attractive young-ladyhood) and cowering in there, denying both her childhood and her approaching age.
Susan may have represented the majority of humans in this world, but that's Lewis' point. We all have a tendency to trade in the beauty of true, deep reality for the trite and worthless. For another example of this, look at the introspection of Mark Studdock at the end of
That Hideous Strength. Trapped by his enemies and facing (he thinks) death, he realizes that all his life he's traded what he really wanted for what he thought would impress others:
He saw himself making believe that he enjoyed those Sunday afternoons with the athletic heroes of Grip while all the time (as he now saw) he was almost homesick for one of the old walks with Pearson - Pearson who he had taken such pains to leave behind. He saw himself as a teen laboriously reading rubbishy grown-up novels and drinking beer when what he really enjoyed was John Buchan and stone ginger. The hours that he had spent learning the very slang of each new circle that attracted him...When had he ever done what he wanted?
If we're going to learn a lesson from Lewis through the character of Susan, let's remember to keep our eyes on the eternal, the significant, the holy, the "deep", and not be distracted by tritisms of the world, whatever form they come in.