Steve Burton and Estranged Wife Sheree Were in a 'Coasting Stage for a While' Before Split: Source

Steve Burton and wife Sheree (Gustin) Burton had experienced obstacles in their relationship before their eventual split.

Amid their 23-year-long marriage, the twosome faced hardship after Steve, 51, was let go from his role as Jason Morgan on General Hospital in November 2021. Steve's firing came after he chose to not abide by the production's COVID-19 vaccination rule.

"Their lives were changed when he went through some upheaval and anger over what he considered his freedoms being in jeopardy," a source tells PEOPLE exclusively. "He had to leave a show that he loved, which caused chaos in his life."

According to the insider, Sheree had become "unhappy" leading up to the split and was looking for "something more."

"Their lives have been in the coasting stage for a while," the source says. "After a long marriage, it's not that unusual."

PEOPLE has reached out to Steve and Sheree's reps for comment.

Though Sheree announced the pair were expecting a fourth child, when Steve announced the pair's separation on May 4, he also revealed that the child Sheree is currently expecting is not his own.

"I wanted to clear something up. Sheree and I are separated," he wrote on his Instagram Story. "She recently announced that she's expecting her 4th child. The child is not mine."

Steve added, "We are still co-parenting our three beautiful kids. We would appreciate privacy at this time. Much luv, Steve."

The source tells PEOPLE that "it was very strange for someone like Steve to announce this publicly, but the marriage has been just coexisting for a while."

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"They have grown apart but are doing everything to protect the children and keep things as normal as possible," the insider adds.

Steve and Sherre had been married since 1999. They share daughters Makena, 18, and Brooklyn, 7, as well as son Jack, 16.