Rimes announced on Thursday (August 30) that she had checked into an in-patient medical facility to ease "anxiety and stress".
The singer's revelation that she is seeking treatment led to media speculation that Cibrian may have cheated on her, with someone supposedly close to the couple claiming that Rimes recently confided similar fears to friends.
"LeAnn called a friend of hers a few weeks ago sobbing hysterically about Eddie going out," an insider told Radar Online.
A spokesperson has now dismissed rumours of infidelity in a statement to Gossip Cop.
"There is absolutely no truth to that story whatsoever," Rimes's spokesperson insisted.
Rimes took legal action on Thursday against two women who allegedly illegally taped phone conversations with the star and then uploaded portions of the chats on the internet.
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