"Nicole knew very well that having Paris involved would have inevitably turned a special night into being about their friendship," a source tells UsMagazine.com. "Nicole's life is completely different now."
In fact, Richie didn't even bother to invite Hilton, her best friend since the age of 2, to attend the winter-themed ceremony. And though Richie's pals Khloe Kardashian and Samantha Ronson made the final guest list, a source close to Hilton tells Us that the 29-year-old socialite "isn't dwelling on it too much."
"She and Nicole aren't close anymore, but there are no hard feelings there," the insider explains. "They just grew up and apart."