Deep in the throes of preventative chemotherapy treatments, Kate, Princess of Wales, is “determined” to show everyone she hasn’t given up. “It showed a lot of courage and character, as she knew that the world was watching,” royal author Robert Jobson said of HRH as she attended the Men’s Final portion of Wimbledon on Sunday, July 14. “This will have given her sustenance,” a palace insider told People. “She has gone through something awful and stressful, and it is crucial to have little wins to look forward to or to give you the courage and energy to go forward. And this was it.” The future que…