Colton Underwood, a star of “The Bachelor” and a former football player, came out as gay in an interview with Robin Roberts that aired Wednesday on “Good Morning America.”

He described 2020 as a year of self-reflection, one that “probably made a lot of people look in the mirror and confront what they were running from or what they’ve been putting off in their lives.”

“I’ve ran from myself for a long time,” Mr. Underwood, 29, said in the interview. “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, and the next step in all of this was sort of letting people know.”

He said that coming to understand his sexuality has been a “journey,” and now he is “the happiest and healthiest” he’s felt in his life. He had reached a low in 2020, he said, that led to thoughts of self-harm and suicide.

“I got to a place where I didn’t think I was ever going to share this,” he said. “I would have rather died than say, ‘I’m gay.’ And I think that was sort of my wake-up call.”

In his 2020 memoir, “The First Time: Finding Myself and Looking for Love on Reality TV,” Mr. Underwood described being confronted by his parents about his sexuality as a teenager.

“‘You know, Colt, we’d still love you and support you if you were gay,’” he recalled his mother telling him.

His father was more confrontational. “He’d pulled up the history of recent Google searches, which included gay porn sites and a variety of questions: ‘Am I gay? How do you know if you’re gay? Why don’t I like having sex with my girlfriend?’” Mr. Underwood wrote in the book. “At first, I denied responsibility. Then I owned up to having been curious. He asked if I wanted to talk about it. I said no, explaining that I’d figured things out on my own.”

Mr. Underwood appeared on “The Bachelorette” in 2018 and quickly became a fan favorite on the reality dating show. But Becca Kufrin, the season’s star, worried that he was unprepared for a lifelong commitment and eliminated him after their “hometown” date, where she met his family. (The show’s producers had made Mr. Underwood’s sexual inexperience a major plot point.)

He starred on “The Bachelor” in 2019, where again his virginity was a central theme. Near the end of the season, as the stress of the show increased, he said he was “done” with filming and “jumped the fence” of a resort in the Algarve region of Portugal in an effort to escape the set.

After the show ended, Mr. Underwood and Cassie Randolph, 25, the front-runner of his season, began dating. Ms. Randolph’s family helped him recover from Covid-19 in March, around the time his memoir was published.

The couple announced their split in May 2020. In November, Ms. Randolph filed a restraining order against Mr. Underwood, who she said had placed a tracking device on her car. Viewers of his “Good Morning America” segment inferred that this was the personal low to which he was alluding.

In its 20 years, the “Bachelor” franchise has never featured a gay cast.