The resolution (or closing point) of the novel is:

This would be in the epilogue of the book. After Charlie mails the last letter, he loses his ability to recall anything until he wakes up at a doctor's office. He has been in the hospital for two months, and for the first week he was there, he didn't speak to or acknowledge anyone who came to visit him. He was sent to the hospital after his parents found him sitting naked on the couch watching television, without the television on.

While Charlie is in the hospital, he realizes that everything he dreamt about his Aunt Helen is true and that it happened every Saturday when they watched television. Working through these things is very difficult, but Charlie's visitors help a lot. His family and Patrick visit frequently, and Patrick brings letters from Sam. These are the things that help Charlie the most. Ultimately, Charlie doesn't want to blame his Aunt Helen for the way he is - he realizes that he has agency and power, and that while his background factors into who he is, he still has control over his own life.