It's been a couple years since I read it last. It had been long enough that I could only remember the big moments, but as soon as I jumped into a scene the memories came flooding back, not unlike our hero sitting in front of the pond. I was looking for clues this time, some sort of tell that would give me the definitive answer about it all and clear up the vagueness of the ending, but I didn't find any, probably because that's not the point of the book.
Sure, it can be read as straight magical realism, in which if you don't ask for too many explanations about the world into which you've been dropped, you can enjoy it for what it is: a tale of a scared little boy on the edge of a magical world and how his interactions with it shaped his life. But the problem I have with that interpretation is that the story doesn't offer anything beyond that in way of trying to explain itself. Even as an adult, he doesn't offer much perspective on his childhood memories. Which for me is sorta the point of it all.
He's telling a story.
I came away thinking that it doesn't matter if those things actually happened to him, and they probably didn't. Those stories were simply ways for him to gain perspective on his childhood traumas, a coping mechanism from a precocious mind.
The point of it all is that there is healing in the storytelling, that's why we do it, sing songs and watch movies. It's why we create art, isn't it?