There is no problem with Susan.

The problem is with the people who criticise a writer for saying something that they don't like, or condemning a writer for what they assume he said (when he did not say it).

The problem is with people who failed to read the whole series, and to understand the links between our world and Narnia, or Christian faith and belief in Aslan.  Not all readers or lovers of Narnia have Christian faith, but if people have open minds they can see what was really said in the books. (Nowhere do the Seven Friends of Narnia accuse Susan of having a string of boyfriends, being nasty, or anything more than denying what she once believed, and acting like an empty-headed girl at her worst age !- perhaps to fit in with a different crowd?)

actually, I read somewhere that Lewis was going to write a book covering Susan's life but he ended up dying before he could.

@frederick one of my online friends has suggested that there is a similarity between Susan Pevensie and the young woman in That Hideous Strength (the third of Lewis's Space Trilogy). Her name is Jane Studdock  and she and her husband each look for meaning and purpose in their lives. 

Jane seems to be very much on her own, and has no faith. (I must reread this, and collect more information to put on here!)

Lewis wrote the Space Trilogy in the early 1940s. Susan had not yet been thought of, but what became of her might be very similar to Jane's situation (not actually being Jane!).

I didn't know that. Of Lewis's non-Narnia work, I've only read Out of the Silent Planet and that was a while ago. I need to re-read it, I remember the striking beauty of the language.

@cobalt-jade it's worth the effort to read all three. THS has links to the other two, but is somewhat different, and some people like it best. 

@coracle oh i didn't know that. i haven't checked out any of his non Narnia works. Thanks for the rec.

Posted by: @frederick

actually, I read somewhere that Lewis was going to write a book covering Susan's life but he ended up dying before he could.

Perhaps you were thinking of what Lewis wrote to a young reader who asked him if he would write a sequel about Susan, and he said he wasn't planning to for this reason:

Not because I have no hope of Susan ever getting to Aslan's country, but because I have a feeling that the story of her journey would be longer and more like a grown-up novel than I wanted to write. But I may be mistaken. Why not try it yourself?

(Unfortunately I can't find the source for that quote — I've just copied it from one of the first pages in this discussion — but I have definitely seen it quoted in other places as well.)