The 28-year-old actress wasn`t a popular teenager and admits she didn`t fit in with the various peer groups and preferred to spend her time reading books.
The Hollywood beauty - who moved around a lot as a child because of her father`s job, but spent the majority of her youth in Massachusetts and Connecticut - said: "I was a real loner in highschool, even though people assume I was the head cheerleader. My head was always in books. I felt uncomfortable in cliques. I wasn`t a social butterfly at all."
Kate admits her situation didn`t really change when she went to New Jersey to study at Ivy League college Princeton when she was 18.
Although most people have a crazy time at college, the `Straw Dogs` star still preferred studying to partying.
In an interview for the 15th Anniversary Issue of BlackBook magazine, she added: "Talk about anxiety! That was a really stressful time for me. I look back now and think, `How did I ever do that?` I lived there, in a tiny studio apartment, on my own."