"Hey, I fully understand and deserve ur anger & disappointment towards me, but please leave [Tom] Schwartz, my friends and family out of this situation," he wrote on Instagram. "This was a very personal thing."
He also offered employees of his new restaurant Schwartz and Sandy's an apology for how his actions may have impacted the business.
"They did nothing wrong," he said. "I'm so sorry that my partners, Greg, Brett, Schwartz and our employees have to suffer for my actions. I will be taking a step back & taking a hiatus out of respect for my employees & partners. I need some time to address everything else. Sorry for everything."
Soon after releasing his statement, some of Tom's co-stars reacted to the message on their own social media accounts.
A source close to VPR production confirmed to E! News on March 3 that Tom and Ariana had called it quits. The insider noted that cameras were rolling amid the breakup news, so it's likely that the drama will be shown on a future episode of the Bravo show's current 10th season.
Hours after the breakup made headlines, Ariana was spotted hanging out with friends at the Tove Lo concert at The Wiltern in Los Angeles. Meanwhile, Tom performed with his cover band Tom Sandoval & The Most Extras at The Grove of Anaheim in Southern California.
"He put on a great show," one audience member told E! News. "Unless you know what's going on in the rumor mill, you would never know something was going on." Another eyewitness added, "He came into the crowd after during Yachtley Crew's performance. He smiled and took pictures with everyone and watched the show. He seemed ok."
The couple were together for nine years before going their separate ways. While Tom, 39, has been part of the cast since the series' premiere in 2013, Ariana, 37, joined the lineup in the second season after transferring from another one of Lisa Vanderpump's restaurants to SUR.
Since then, their ups and downs have been documented on the show. Most notably, Ariana and Tom experienced a rift in their relationship during season seven, when the TomTom co-owner told his friends a NSFW story involving his girlfriend and VPR castmate LaLa. At the time, Ariana said that Tom had "betrayed my trust" in sharing the story without her permission, though the two eventually made up.
Earlier this year, the duo denied rumors that they were in an open relationship. After a season 10 trailer sparked speculation about their love life, Ariana tweeted in January, "we dont have an open relationship. i'm really not that cool. thought that was obvious."
Tom also shot down the polyamorous claims, telling E! News last month, "We are not in an open relationship."
He added at the time, "We're both very busy, we both have things going on."
(E! and Bravo are both part of the NBCUniversal family.)