Justin Hartley cold-heartedly fired off a text to Chrishell Stause about filing for divorce … so claims the “Selling Sunset” star.

Chrishell broke down telling co-star Mary Fitzgerald about exactly how she found out the “This Is Us” star wanted out of their marriage. It’s pretty heartbreaking … Chrishell choked back tears before revealing, “I found out because he texted me that we were filed [for divorce].”

The actress/real estate agent says at first she thought Justin was joking but pretty quickly reality set in … adding that “45 minutes later the world knew.” 360aproko broke the story … Justin filed for divorce in November 2019 after 2 years of marriage. She later strongly hinted she was blindsided by the news … and now we know why.

Chrishell says she spoke to Justin after he dropped the bombshell on her but that was the end of their communication. She was clearly distraught … saying even though they were only married for 2 years they were together for 6 years. She said if this is what Justin really wanted “there are better ways to go about it.”

The Netflix hit “Selling Sunset” premieres season 3 beginning Friday … and the season’s storyline largely centers around the sudden end of Chrishell and Justin’s marriage.

That’s playing out pretty publicly — Justin’s moved on and has been photographed getting cozy with a new GF.