Jenna Jameson -- My Creepy Friend Has My Keys ... And I'm Terrified

Legendary porn star Jenna Jameson is scared of the man she says repeatedly broke into her home and threatened to destroy her career ... she claims he's coming after her family and is seeking protection.

A judge gave Jameson a restraining order against Allen Dean Clayborn after she says he stole her house keys and took cash from her home. Jenna says he's also threatened to take her down through blackmail and spreading lies to the press.

Jameson's so afraid of Clayborn she claims she became extremely ill and she's concerned his actions could affect her ability to see her two boys with ex Tito Ortiz.

Now the twist ... she says they used to be friends ... but it's not clear when things took a dark turn and got crazy.