“Real Housewives of New Jersey” star Teresa Giudice headed to the slammer reeling from the cruelest betrayal yet by her cheating husband – he plans to divorce her while she’s behind bars!

Teresa, 42, received word “Juicy Joe” was “going to dump her” as soon as she began serving her 15-month jail sentence on Jan. 5, sources close to the couple exclusively told The National ENQUIRER.

“Teresa’s last Christmas with the kids before jail was further destroyed when she found out about Joe’s evil plan,” a source said.

“She angrily took off her wedding ring and nearly broke down.”

An insider said the couple owe more than $13.5 million and were “sleeping in separate bedrooms” at their New Jersey mansion before her incarceration in a federal prison in Danbury, Conn.

“Joe plans on filing for divorce as soon as Teresa goes to prison. He feels it will be the perfect time because she’ll be limited in what she can do from behind bars, and that will give him the advantage,” confirmed the insider. “As shocking as it is to believe, Joe blames Teresa for all their legal problems and wants to get on with his life.”

Joe, 44, must serve his 41-month sentence after Teresa’s release. He also faces possible deportation to Italy, where he was born, because of his federal conviction.

The two were accused of illegally netting $5 million over 10 years. They were convicted of bankruptcy fraud, conspiracy to commit mail fraud and wire fraud, bank fraud and making false statements on loan applications.

The ENQUIRER has reported that Joe cheated on Teresa with “a sexy college student.” In 2012, he referred to Teresa on their TV show as “my b—h wife … she’s such as c–t.”

Said the source: “This is the cruelest betrayal Joe has ever perpetrated on Teresa. The thought that he wants to divorce her while she’s in jail is disgusting. She was counting on him to look after their four daughters – ages 5 to 13 – while she’s behind bars.”