"Tristan had no interest in going, but Khloe insisted on it," a source told Heat.
"Her sister Kim advised her that it was a good idea, because their relationship was already going to be a challenge with a new baby around, let alone a cheating scandal hanging over their heads."
As RadarOnline.com reported, Thompson, 27, was spotted cozying up to another woman in New York City just days before 33-year-old Kardashian gave birth to their daughter, True, on April 12.
"The sessions have been difficult," said the source of the couple's "frank discussions" behind closed doors with a professional mediator. "Their fights are monumental at the moment."
But at home in Cleveland, continued the source, "they barely talk — except when it comes to the baby — but there have been some very frank discussions during the session."
Despite their intense sessions together, the prognosis for Kardashian and the NBA basketball player isn't good.
"The relationship seems unlikely to survive," said the source. "Friends think there's no way Khloe wants to raise her daughter in such a toxic environment."
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