Hilary Duff and Mike Comrie shocked fans last week by announcing they were splitting after three years of marriage.
What went wrong between the pair? According to Us Weekly, Hilary and Mike attempted to save their marriage through therapy.
"[Hilary] felt he didn't put enough effort into the relationship," a source told the mag.
The couple, who are parents to son Luca, tried marital counseling for a year-and-a-half, but - according to the source - Mike "wasn't doing any of the things they'd worked on."
"The spark was no longer there," another source told the mag. "They are better as friends."
As previously reported on AccessHollywood.com, Hilary, 26, and Mike, 33, announced they were splitting on Friday.
"[They] have mutually decided [upon] an amicable separation," Hilary's rep told Access at the time.
"They remain best friends and will continue to be in each other's lives. They are dedicated to loving and parenting their amazing son, and ask for privacy at this time," the rep added.
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