Lindsay Lohan and Mary-Kate Olsen are at war over custody of a life coach. Mary-Kate is royally pissed that LiLo has been secretly seeing her life coach, Lori Cerasoli.

“Lindsay has been seeing Mary-Kate’s counselor Lori Cerasoli, and MK isn’t happy about it,” an insider tells Star.

Lori has been counseling Lindsay through her well-documented battle with drugs and alcohol-and the road to sobriety doesn’t include an additional line for the petite billionaire.

“Every time Mary-Kate wants to get hold of Lori, she feels like she’s with Lindsay. Mary-Kate called Lindsay and told her to get her own counselor,” the tabloid source says, adding that there’s little chance Lindsay will allow Mary-Kate more time with their coach.

“Lori can only work with one client at a time-and right now she’s with Lindsay, who has no intention of giving her up!”