Heartbroken  DOLLY PARTON wages desperate battle to get justice for a vicious sex at­tack that has rocked her world, according to court documents.

The country music legend was stunned by terrifying allega­tions that her brother Denver’s daughter, Jennifer Parton, was assaulted by the son of a former employer – and now for the first time the full shocking story has been uncovered by a bombshell ENQUIRER investigation.

We’ve exclusively obtained explosive court papers in which Jennifer describes the alleged attack that, sources say, nearly destroyed her marriage and left her with deep psychological wounds. And we learned how devoted Dolly, 67, rallied to Jen­nifer’s side, urging her to seek justice.

“WHEN DOLLY HEARD Jen­nifer’s heartbreaking story about how she was assaulted, she went on the warpath to make darn sure justice was done and her attacker was made to pay,” charged a source close to the Parton family.

Dolly has already experi­enced a similar heartache. As The ENQUIRER reported in January 2012, her sister Stella, 63, claimed that she was sexu­ally assaulted by a wealthy politician from her hometown Sevierville, Tenn., when she was 24.

“Dolly, who’s never had a daughter or son, has a very spe­cial bond with her nieces and has taken Jennifer’s ordeal very hard,” said the source.

“She’s showered Jennifer with her love and support and has offered to help get her counsel­ing or anything else she needs to put the nightmare experi­ence behind her.

“Dolly has known the al­leged attacker’s family for many years, so it comes as an even greater shock.”

Jennifer hit back at her al­leged attacker Chase Pipes with a civil suit filed in federal court against Smoky Mountain Knife Works, Inc., her employer for 15 years, and Pipes, the 29-year-old son of the company’s founder.

Jennifer, 38, once shared an office with Pipes and says her nightmare began unfolding in June 2008 when he started placing personal letters on her desk, exposing his “amorous in­tent,” according to the suit.

She complained to her super­visor but says she was told “it would be unwise to show the letters to the owner of the com­pany.”

Pipes not only continued his pursuit, it grew fright­eningly bizarre, a shaken Jennifer charged, claim­ing he “began fantasizing about getting a divorce in order to start a rela­tionship with her,” even though she let him know she was happily mar­ried.

Pipes grew agitated  when he learned she had begun fer­tility treatments to conceive a child with her husband, according to the suit, and he allegedly responded by indicating “if she would leave her husband he would provide her with a better life.”

He turned up the pressure, say the papers, continuing to pursue her and telling her “his father would be retiring soon and if she would begin a relationship with him and bear his child he could provide her with all the security she would ever need.”

A BADLY SHAKEN JENNIFER says she continued to complain to her supervisor, and Pipes was eventu­ally required to apologize and vacate their shared office.

A few weeks later, Jennifer claims she received a jarring text message from Pipes’ wife, accusing her of be­ing a “home-wrecker.”

After Jennifer filed numerous ad­ditional complaints, Pipes suddenly and unexpectedly made a show of goodwill – offering her “the use of his father’s farm to stable her horses for the winter free of charge,” according to the lawsuit. But Jennifer says after she arrived at the farm to meet the manager, Pipes asked her to come in­side and look at his son’s room.

That’s when all hell apparently broke loose.

“As soon as Jennifer walked into the house, Pipes grabbed her from behind and bound her arms with a cloth rope,” say the court documents.

“Jennifer protested and asked him to refrain, but Pipes dragged her to his bedroom and forcibly began to kiss her neck. She fought back by biting him. To subdue (her), Pipes grabbed a shirt and placed it over her face.

“Allegedly, Pipes then forcibly pulled down (her) pants and sexually assaulted her. (She) then replaced her clothes and left the building.”

Jennifer called her physician, who advised her to go to the emergency room, according to the documents.

Unless weapons are used in the as­sault, victims are not required by law to cooperate with law enforcement, according to experts contacted by The ENQUIRER. Jennifer did not file criminal charges – and that deep­ly upset her famous aunt.

“Dolly couldn’t convince Jennifer to press charges no matter how hard she tried.”

The civil suit was settled out of court in October, but terms were not released.

Tragically, Jennifer, who left her job, has spiraled downhill, say sources. Following her ordeal, her marriage broke down and she was diagnosed with post-traumatic stress disor­der by two separate physicians “for which she continues to seek medical treatment,” according to the suit.

The source added that newlywed Jennifer was overcome with grief at the very time she was trying to start a family and shelved those plans to deal with her trauma.

“She was deeply affected by the attack and it nearly wrecked her mar­riage,” continued the source.

“Jennifer is doing everything she can to put the pieces of her broken life back together, but it’s still a con­stant struggle. Thankfully, Dolly was there to counsel her the best she could.

“Dolly won’t ever stop trying to help Jennifer.”