Bachelor in Paradise: Blake Horstmann Never Meant to Hurt Caelynn by Exposing Texts, Source Says

For Blake Horstmann, Paradise has become more like hell.

“He’s really not doing well,” a source tells PEOPLE of the drama that’s seeped off-screen.

The Bachelorette star won hearts as the runner-up on Becca Kufrin‘s season, and he arrived on Bachelor in Paradise as the most sought-after guy on the beach. But during this week’s two-night premiere, he was slammed by fellow contestant Caelynn Miller-Keyes for hooking up with her one day after sleeping with Kristina Schulman at the Stagecoach music festival in April. Miller-Keyes, 24, tearfully told cameras he’d called their night together a “mistake” and begged her to keep the tryst a secret.

“I feel like a slimy, disgusting secret that you’re ashamed of,” she cried during Tuesday’s episode.

But as the scenes aired, Horstmann, 30, posted text messages that seemed to debunk her story, suggesting she sought him out for sex and was stressed about people finding out. (She has not returned PEOPLE’s request for comment.)

The source tells PEOPLE that Horstmann didn’t make the decision to publicize their conversation lightly — and is upset that some fans are now attacking Miller-Keyes.

“It was very, very difficult for him to put that out there. Putting the text out there was never about hurting Caelynn. He felt like his hands were tied and it was the only way to tell his truth,” the source says. “Blake is such a sweet person. He feels so bad about the hate that she’s getting. It’s not about him against her, he felt like he was just being completely painted in lies.”

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Horstmann deleted the text screenshots later Tuesday night.

“This is the last thing I wanted to do, but my name and character are being attacked. My name is all I really have,” he had said on his Instagram Story. “Most of all, it is the only real way to prove that what is being said by Caelynn and the story that is being shown is far from the truth. I’m deeply sorry for my actions at Stagecoach but telling the world that I silenced a woman amongst many other harmful accusations was just too much.”

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And on Tuesday’s episode, he broke down. “I’m going to have to really go into hiding, I know I am,” he told producers, sobbing. “It’s going to be hard on everybody in my life, because of what I did. … This is real life. I know this is television, but it’s my life.”

The scandal has shaken Bachelor Nation, with many franchise stars supporting Horstmann on Instagram. However, BiP‘s Dean Unglert, who sources have said is dating Miller-Keyes post-Paradise, criticized him as “childish.”

Bachelor in Paradise airs Mondays and Tuesdays (8 p.m. ET) on ABC.