When dealing with a break-up, it's always nice to have people who you can count on to support you. For Kourtney Kardashian, she's got her sisters to help keep her mind off her recent split from Scott Disick.

Kourtney spent the morning working up a sweat with her sisters Kim and Khloe Kardashian. In the evening the trio hit the town looking absolutely angelic in radiate white dresses. It was Kourtney's first appearance in public since news of the split broke on Monday, and she looked like she was ready to have a fun night.

WATCH: Kourtney Kardashian Splits From Scott Disick After He's Spotted With Another Woman

The sisters, who were filming an upcoming episode of "Keeping Up With the Kardashians" while going out for a girls' night at Casa Escobar in Westlake, California, shared a cute selfie on Instagram.

IDFWU!!!!!

A photo posted by Khloé (@khloekardashian) on

With their tongues out, it's hard to imagine the girls weren't sending a message to Kourtney's ex.

WATCH: Scott Disick Gets Touchy-Feely With a Woman Who Isn't Kourtney Kardashian

Meanwhile, Scott didn't seem too upset about the split. The 32-year-old broke his social media silence with an Instagram post on Tuesday encouraging his followers to "party with me this Friday in Vegas."

Kourtney and Scott, who were never married after dating for nearly 10 years and have three children -- Mason, 5, Penelope, 2, and Reign, six months -- reportedly split up over the Fourth of July weekend, possibly due, in part, to photos that showed Scott getting close with his ex-girlfriend Chloe Bartoli in Monte Carlo.

WATCH: Scott Disick's Ex-Girlfriend, Chloe Bartoli, Attacked on Social Media Following Kourtney Kardashian Split

A source tells ET that Scott has been spending time with friends who "are not a good influence," which may have also contributed to the split.

Scott and Kourtney broke up once before in 2010 because of his alleged alcohol problem before reconciling. In March, Scott entered a rehab facility in Costa Rica.

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