Not that this dampened the spirits of the Jimmy Kimmel Live host, 40, who celebrated on the air with a video starring Richard Simmons, seen here.
"Almost everyday," he told PEOPLE at the party, "I step back and I go, 'I can't believe that this is happening.' It's especially weird when I see my Uncle Frank mingling with celebrities, because it just doesn't make any sense."
More family-festooned than star-studded, the subdued affair poolside at the Roosevelt Hotel (with a bottle of Jameson Irish Whiskey on every table) attracted its fair share of Kimmels, as well as Rebecca Romijn, Adam Carolla, Dominic Monaghan, Rachael Harris and Kid Rock.
Not in sight: Matt Damon, or Ben Affleck -- despite their recent comedic contributions to Kimmel's show.
Silverman and Damon, however, had taken out a trade-paper ad earlier in the day congratulating Kimmel on his broadcast landmark and also further fueling rumors of their own faux-mance.
"The Variety ad?!" said Kimmel. "That was a surprise to me. It was funny, I thought it was great. I was in my office, this morning, I had no idea. I was just reading, but I was pleasantly surprised by it. I actually thought that it was cute."
According to Silverman, 37, "It was Matt's idea to go in together on a page, and I had this tennis picture, so ... ."
Yet, when it came to giving Kimmel something to celebrate his show's 1,000th, she said: "S---, I really didn't get him anything. That Variety thing really put me out. I'm the poorest celebrity in Hollywood, if you can even call me a celebrity." --Reagan Alexander and Stephen M. Silverman