The pair separated after two years of marriage last week.
Last week, a source confirmed to ET that the pair separated after two years of marriage, noting that the couple -- who tied the knot in May 2021, five months after announcing their engagement -- "ultimately were just not a good fit."
A separate source tells ET that Gomez wanted to make things work with the Wicked actress and still considers her his partner.
"Dalton is having a hard time after his breakup with Ariana. It has been a difficult time for him because he wanted to make things work," the source says.
Gomez had even traveled to Europe recently to be with Grande to try and work things out between them, to no avail.
"He still has a lot of love for her and still considers her his partner, but she has moved on," the source continues. "Dalton's friends are encouraging him to do the same."
And move on she did, with a source confirming to ET just three days after her split from Gomez that she's dating her Wicked co-star, Ethan Slater.
"Ariana and Ethan recently started dating. They have a lot in common and have a lot of fun," the source said. "They didn't start dating until both were broken up with their significant others. Ariana and Dalton remain friends."
Slater plays Boq in director Jon M. Chu's upcoming adaptation of the beloved musical -- a Munchkin who is deeply in love with (but ultimately, romantically rejected by) Galinda, played by Grande. (Boq later becomes the Tin Man as Wicked sets up the world of The Wizard of Oz.)
The news has been hard on Slater's ex as well, with a source telling ET that his estranged wife, Lilly Jay, is "devastated" by the breakup with her husband.
Slater married Jay, his former high school classmate, in 2018. The couple welcomed their first child, a son, last year. In November 2022, Slater shared an anniversary tribute to his wife on Instagram, writing, "My best friend. 4 years married, 10 years together. And this is easily the best (and most *bizarre*) year yet." Grande liked the post.
"This is not the future she had in mind," the source added. "She's doing her best to get back on her feet. She's incredibly smart and driven" and "she is truly the best mother."
For more on their divorce and Grande's new relationship, check out the video below.