Suggest me books with main focus on character introspection!

I love the psychological genre and am looking for more books to check out. To make it easier to suggest a book for me here are a few books I have loved! The first is The Secret History by Donna Tartt. It was intriguing to read knowing Richard was an unreliable narrator. Especially one with a rose-colored lens towards the group around him. Despite the obvious damning flaws within them all.
Another book I enjoyed is “I’m Thinking of Ending Things” by Iain Reid. I found the back-and-forth of the story and the little interview segments to be fascinating, considering what it all built up to.
The book that got me into reading more and that I enjoyed heavily is “Solaris” by Stanislaw Lem. I found the premise to be enthralling with a place being able to manipulate thoughts and memories.