Demi Moore Returns to L.A. after Treatment

A healthy-lookin' Demi Moore touched down in L.A. on a private jet last night ... the first time she's been seen in public since her whip-it induced medical emergency back in January ... and TMZ has the pics.

Moore -- who was reportedly vacationing in Turks and Caicos following a stint in treatment -- was greeted with a big 'ol bear hug by a mystery woman who was waiting on the tarmac.

Moore had been off the radar ever since the January 23 incident ... when she was hospitalized for seizure-like symptoms after inhaling nitrous oxide at her L.A. home.

Demi's rep said the actress was seeking "professional assistance" to treat exhaustion and improve her overall health ... but wouldn't reveal where she got treatment.