Caitlyn Jenner -- I'm a Wine and Champagne Gal, Now!

Caitlyn Jenner's gotten much looser with her attitude toward booze in the weeks since saying goodbye to Bruce.

Bruce was always very health conscious, and would only drink the occasional beer -- but our sources say Caitlyn's now a connoisseur of wines and champagnes ... relaxing with a few glasses while hanging with her girlfriends.

And CJ's not just highfalutin -- we're told she did down a few shots too at The Abbey over the weekend.

Our sources say people in Caitlyn's life have noticed she is drinking more, but no one thinks it's an issue in the slightest -- she's just finally comfortable living her authentic life.

Case in point ... on Monday she was still toasting her ESPY with GFs. #YOLO