Jenna Dewan Was the Last to Know About Ex Channing Tatum's New Relationship

When it came to Channing Tatum moving on from his ex, Jenna Dewan was the last to know.

In Dewan's upcoming wellness book Gracefully You: How to Live Your Best Life Every Day, she explained how she felt "blindsided" by the news that Tatum was in a new relationship with Jessie J. The pair were first spotted together in October 2018.

"I was learning things about my ex most people wouldn’t have to face–and over the internet, as it was happening," wrote Dewan about the shocking revelation, shared in an excerpt from E!.

"There I was, on a plane, alone, finding out about his new relationship. I felt blindsided. Choosing grace as I learned everything about my personal situation along with the rest of the world was really difficult."

RELATED: Channing Tatum and Jenna Dewan Are Legally Single, But Not Officially Divorced

But even though she was left reeling by Channing's decision to move on (and how awkward finding out was for her), Jenna eventually fell in love again. She's now in a relationship with actor Steve Kazee, and the two are expecting their first child together.

"When I was ready, I started dating someone amazing,” she wrote, according to E!. "It was this cosmically great thing where we circled back around each other after a moment of instant recognition years ago."

As far as Channing's new fling, he had ended up in a new relationship just months after he and Jenna announced their separation in April 2018. The pair had been married for nine years and officially filed for divorce on Oct. 26, citing irreconcilable differences.

But despite the fact that Jenna felt surprised by Channing having moved on so quickly, she was quick to support Jessie J in the past as internet denizens began to compare the pair's looks.

"FIRST OF ALL...whenever I hear of the 'striking resemblance' w/ Jessie J and Jenna Dewan my only thoughts are ummmmm no [laughing emoji] not even close," the fan wrote. "And I don't have a horse in the race but gf you are untouchable. Just trying to spread positive vibes, keep doing you...to an absolute outsider from a small town do are doing it seemlessly [sic]," one fan wrote.

Dewan replied simply "positive vibes all the way" at first, while Jessie J snapped back with a lengthy Instagram response on her own, talking about how she was "embarrassed" and "disappointed" by the situation.

"Amen Jessie! Yes!!!!!" Jenna replied on Instagram. "Women for women all the way. No need for negativity. Let's live in a world where we support each other and raise each other up. Like i said before, positive vibes all the way. Nothing but respect [heart emoji]."

There's likely even more to the story in Jenna's upcoming book, and we can't wait to read it.