An aide to Rosenberg on Thursday confirmed that Rosenberg and Hefner are no longer living together.
The separation comes amid an ongoing investigation into whether Rosenberg or his staff violated Senate rules in connection with allegations against Hefner.
Several men told The Boston Globe they had been sexually abused by Hefner.
Rosenberg had previously said his husband planned to enter in-patient treatment for alcohol dependency.
The Amherst Democrat stepped aside as Senate president, at least temporarily, as the committee conducts its investigation. Worcester Democratic Sen. Harriette Chandler was elected to fill the post of president during the interim.
The committee said it will release the report publicly while protecting the identities of victims and witnesses.
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