YA Arthurian Mental Illness

I read this as a paperback (likely an advance copy) in about 2000, give or take a couple years either way.

It was not part of a series.

It was set in modern (at least the last 1/3 of the 20th century) Britain. I believe it featured a teen who may have been mentally ill who came to believe he was part of Arthurian legend, possibly believing himself to be Merlin. Over the course of the book I am pretty sure he makes his way to Glastonbury Tor.

This wasn't really a fantasy book, more of a psychological thriller with fantasy (or hallucinatory) overtones.

I know there are MANY Arthurian books out there, so I'm hoping someone here can help me find this needle in a haystack. Thanks in advance for any help you can provide.

Corbenic?

That looks like a very good bet to be it! Thank you very much.

It sounds so amazing, it's going on my TBR list, too.

After a little closer look I'm sure this is the book I was after, so great job rarm!

When I first read this I had somewhat mixed feelings. The protagonist is difficult. That said, it's an original take on Arthurian themes. In my less-than-perfect recollection it's a smart and genuine take on those themes.

It definitely stayed with me, and I'm looking forward to reading it again.

Hooray, glad that it's the one. I haven't read it but it's on my never-ending list of Arthuriana-to-read.