Jenna Dewan is reportedly upset that her soon-to-be ex-husband Channing Tatum has moved on so "quickly" with Jessie J.

Jenna Dewan

Jenna Dewan

The 37-year-old actress recently filed for divorce from Channing - with whom she has five-year-old daughter Everly - following their split in April, and although she has just started dating Tony Award-winning actor Steve Kazee she has been shocked by how serious his new relationship with the British pop star has gotten since they got together a few months ago.

A source told Australia's New Weekly Magazine: "Although they're acting like it's still pretty casual, they're actually very into each other. It's got to be painful [for Jenna] to see Channing moving on in this way. Although they're both dating, she didn't expect him to get serious with someone else this quickly."

And Jenna is said to be dreading the moment Channing, 38, and Jessie, 30, decide to go public with their relationship and tell the world they're an item.

The source added: "When Channing and Jessie do decide to go public with their relationship, that's going to be tough for her to come to terms with."

The 'Magic Mike' hunk has been showing his commitment to Jessie by "flying around the US" to support the 'Bang Bang' hitmaker at her concerts.

Channing attended Jessie's show in Houston, Texas, on Sunday (28.10.18) and is "working around the clock" to ensure he's still a doting father to his daughter Everly, whilst also spending as much time as he can with Jessie.

A source said: "Channing is like her biggest fan. He flies all over the US to attend her concerts. He works around the clock, loves being a dad and has a decent relationship with Jenna. Jessie J is also dedicated to her career and has a real sense of humour. She likes to have a good time. It is an exciting time for both of them.