During the course of the Netflix reality dating series, Cuevas struck up a relationship with Batten, and even proposed. However, the pair called things off and broke up on the show. After production wrapped, Cuevas began dating Chamblin, another contestant on the show.
A source tells ET that Mark and LC became good friends in the last year and were casually dating, before splitting up over this past weekend.
"It was never serious, but LC saw photos of him with another woman while on a trip and felt betrayed,” the source explains. The source believes that there was a misunderstanding between the duo on the seriousness of the relationship, one side believing it was more than just casual dating.
Over the weekend, Chamblin reportedly learned -- via a post on Reddit -- that Cuevas was dating someone else without her knowledge, and she responded to the thread writing, "I definitely just broke it off with mark so I really do appreciate you posting this and saving me the energy on dating another liar."
In a statement to ET, Chamblin shared, "Mark and I were casually dating, but talked about remaining exclusive, especially because of COVID-19, but that’s over now."
"The main thing I learned from the show and past relationships is that I deserve to be treated like a priority, and not an option," Chamblin added.
Cuevas, meanwhile, told ET, "I enjoyed spending time with LC for a few weeks, but at no point were we in an exclusive relationship, as LC confirmed herself."
"I wish her the absolute best," Cuevas added.
As their breakup played out in the spotlight, Batten addressed the drama when she commented on an Instagram post about the split.
Another Instagram user alleged, "Mark was sleeping with MULTIPLE women at the studio he trained at DURING the show. Maybe show those interviews with his workers next time @Netflix."
"Wow. News to me," Batten replied, in an exchange captured by Comments By Celebs. "I only know about one."
A source close to Cuevas tells ET claims that he slept with someone else during filming of Love Is Blind are "not possible." The source says that Cuevas loved Batten and wanted to marry her.
ET has learned production on the show was intense and cast members were closely followed by cameras all throughout the duration of filming.
ET spoke with Batten in March, and she opened up about her experiences on the show -- including her decision to split up with Cuevas by leaving him at the alter during the show's dramatic finale.
At the time, Batten said that she felt she and Cuevas would stay connected as friends even after the show came to an end.
"We're connected for life because no one is ever going to understand how crazy this was," Jessica shared. "This is season one. This is not like The Bachelor that's been running for, like, 17 seasons. We had to really put ourselves out there and we were in it together. We're always going to be friends for life."
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