Randolph, 25, shared a series of photos on her Instagram Story Thursday and Friday documenting her beach vacation in Cozumel. In one post on her feed, the reality star captioned a picture with her sister, "bffs."
Her posts come after Underwood, 29, addressed his sexuality during a sit-down interview that aired on Good Morning America Wednesday.
"I've ran from myself for a long time. I've hated myself for a long time, and I'm gay. And I came to terms with that earlier this year and have been processing it," he said. "The next step in all of this was letting people know. I'm still nervous. It's been a journey, for sure."
"I'm emotional, but in such a good, happy, positive way," the former Bachelor continued. "I'm the happiest and healthiest I've ever been in my life, and that means the world to me."
Randolph, who has not yet publicly addressed her ex's news, met Underwood as a contestant on his season of The Bachelor, which aired in 2019. He ultimately gave his final rose to her, though they didn't get engaged. The pair dated until announcing their split in May 2020, two months after she helped nurse him back to health after he contracted COVID-19.
Things between them took a dark turn months after they announced their split, when Randolph filed for a restraining order against her ex in September due to alleged harassment and stalking. She ultimately dropped the order two months later.
Amy Sussman/E! Entertainment/NBCU Photo Bank; JC Olivera/WireImage Cassie Randolph, Colton Underwood
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During his interview with GMA anchor Robin Roberts, Underwood was asked about his relationship with Randolph and apologized to her for "how things ended" between them last year.
"I would like to say sorry for how things ended. I messed up," he said. "I made a lot of bad choices."
Amy Sussman/E! Entertainment/ Getty
He went on to say that he had been in love with Randolph, adding, "And that only made it harder and more confusing for me."
"If I'm being very honest, I loved everything about her," he said. "And it's hard for me to articulate exactly what my emotions were going through that relationship with her, because I obviously had an internal fight going on."
He continued, "I would just say I'm sorry from the bottom of my heart. I'm sorry for the pain and emotional stress I caused. I wish it wouldn't have happened the way it did. I wish that I would have been courageous enough to fix myself before I broke anybody else."
During a Wednesday appearance on Extra, fellow Bachelor franchise alum Clay Harbor, who is friends with Underwood, revealed that he had opened up to him about his sexuality prior to the GMA sit-down. Harbor also said he asked Underwood about Randolph during their conversation.
"I asked him if he had told her, and at that time he had said he hadn't and he didn't know if he was going to tell her before or after the interview," Harbor said. "Honestly, we didn't go that in-depth on the Cassie stuff, kept it more on what will happen in the interview, what happens when people find out."