Congrats to David Arquette; he's 100 days sober!

We caught up with Arquette in Hollywood, and he was in a good mood despite the fact his estranged wife Courtney Cox was recently vacationing in St. Barth with her Cougar Town costar, Josh Hopkins.

The Scream 4 star told Ryan Seacrest's KIIS-FM radio show Monday morning of Cox: "We're best friends. We're not together. We're still separated."