What's with the hostility? I don't know Harper Lee and I didn't know Truman Capote, so I don't know the dynamics of their relationship. But I know writers and writer wannabes, and the ones I know love bouncing ideas around. It's much more interesting than talking about the weather.
There are a few novels that, if they ever get written and published, better damn well have my name in the foreword; and if I ever publish one, there are some names I'd better not leave out. It's just part of the process. Look at the relationship between Shakespeare and Marlowe in "Shakesopeare in Love" -- obviously, we can't take that as historically accurate, but Tom Stoppard knows a thing or two about the process.
He was self-absorbed and jealous. He didn't want to hear about her book.
True, after it was a hit. After she won the Pulitzer. After, right out of the gate, she rocketed to the kind of fame he'd worked for and hadn't yet found (though Breakfast at Tiffany's was kinda popular). But why would he be jealous of an old friend's little pet project? And, if the accounts of her helping out with In Cold Blood are true -- the book is dedicated to her, after all -- there couldn't have been that much animosity.
Now, she did have a group of friends who encouraged her and a wonderful editor who should be recognized.
Certainly true. I have a copy of In Cold Blood at my elbow, but I can't seem to lay hands on my copy of Mockingbird, so I don't know whom Lee thanks.
Do I want to argue the point further. No.
When I read your posts, what I hear you saying is that people respond in the same manner. The writers you know bounce ideas off each other...so why didn't they? I don't think they do. I think each individual reacts differently in similar circumstances.
Now, you seem to think that she showed him the manuscript and bounced ideas off of him and got help. Well, okay then.
From the little I read...I just don't. I don't think he wanted to help her.
If we can agree to disagree, I don't think we will have to waste any more bandwidth debating the point.