A source close to the actress tells CNN the split took place earlier this year.
“Michelle and Phil separated at the beginning of the year. It was an amicable spilt and they remain friends,” the source told CNN.
A representative for Williams declined to comment. CNN has also reached out to Elverum’s representatives and are awaiting a response.
Williams described her relationship with Elverum to Vanity Fair as “very sacred and very special.”
The 38-year-old actress, known for her roles on the TV series “Dawson’s Creek” and the film “Brokeback Mountain,” was previously in a three-year relationship with actor Heath Ledger. They had a daughter before Ledger died from an accidental overdose of prescription medication in 2008.
Elverum, frontman for the bands The Microphones and Mount Eerie, lost his wife Geneviève Castrée to pancreatic cancer in 2016. The two had a daughter together.