"A smile hides my pain, a hug masks my heartache, and a laugh covers my tears," Kardashian, 36, tweeted very early Saturday.
A smile hides my pain, a hug masks my heartache, and a laugh covers my tears.— Kourtney Kardashian (@kourtneykardash) March 5, 2016
Her message came days after PEOPLE learned that Disick, 32, had been vacationing in Mexico with Girls Gone Wild founder Joe Francis, a longtime Kardashian family friend.
Kardashian and Disick, who share three children, split in July after nine years together. Before Disick's trip to Mexico, the former couple was spotted getting "flirtatious" while partying with Kanye West.
"Scott's with girls at the house, who are all models and super hot, he's having an amazing time. He's single and doing what single guys do, have fun and hang out with single hot girls," a source told PEOPLE of the Mexico trip. "He is definitely drinking but keeping it under control."
"Scott has been saying how things are much easier now that he's not with Kourtney. She complained way too much and had so many rules," the source added. "She was never happy and he's realizing that now. He's saying how much he is loving life right now!"
However, Disick told PEOPLE exclusively on Friday night that he felt his behavior had been unfairly portrayed in the media.
"The truth is I never lied and said that I was never going to have a beer again," Disick said. "I never said I was never going to have a cigarette again. I never lied and said I was never going to go to the beach again. I never lied and said I was not going to be around my friends and their girlfriends and girls and friends."
"The truth is rehab did help me and now I'm just trying to be responsible," he said. "I'm not out here trying to get wasted, but you know what, I will have a beer on the beach. I'm not doing drugs, I'm not doing anything insane, so I think people just need to relax ... I just want to try to live my life."
Gabe Ginsberg / Getty; Alo Ceballos / GC Images
He said he wasn't sure he could "stay home every single night at 32 years old and be sane."
"In the end, I'm trying to live my life. I'm trying to live it healthy. I'm trying to be there for the people I love, which is Kourtney and kids," he said, "but you know what, we're not together."
"I'm single," Disick added, "and I'm trying to keep my mind off of things ... At the end of the day I think people just need to understand that I have never lied about anything about myself. I am who I am. I do what I do, and enough is enough."
While Disick and Kardashian have been seen together since the break-up, and have worked to co-parent their kids – Mason, 6, Penelope, 3, and Reign, 1 – Kardashian has questioned Disick's recovery.
"He was doing well for a long time. It's sad and worrisome," a source told PEOPLE in February. "[Kardashian] won't tolerate him being around the kids if he is a mess."