On what she likes:
"I truly, genuinely like clothes. Making them is an art form, and wearing them is a form of self-expression. I find it very emotional because I can remember moments in my life--my mood, how I felt--through these clothes."
Her biggest purchase:
"The biggest fashion purchase I ever made I thought about for six years. I'm not kidding. All my life I wanted to own an Hermès Constance bag, and when I signed with Calvin Klein, I decided this was the time that I could afford it. I truly broke a sweat when I paid for it."
Oh, to live Diane's life! (Here's an Hermès bag we can afford.)
And does boyfriend Joshua Jackson share her love of style?
"We go shopping. But he likes it. I definitely wasn't fond of these blue sneakers that he wore all the time for about a year and a half."
On what her favorite look is:
"A well-cut dress. It's all about the cut. I love three-quarter sleeves. I definitely like it classic; less is more. The thing I despise most is vulgarity, and there's a lot of that here [in L.A.]."
Photos by the legendary Ellen von Unwerth.