Gina Lander, 46, was reported missing on March 16 this year by partner David Stokes, 39.
He fell to his death on the M6 in Walsall on April 21 this year.
Today, a coroner ruled that she was unlawfully killed and that David Stokes committed suicide.
No trace of Miss Lander, from New Zealand originally, was found after her disappearance from their home on Mellish Road.
Today West Midlands Police said: "One line of enquiry to date has been that David Stokes may have killed Gina and disposed of her remains shortly before she was reported missing.
"The investigation was handed to the coroner."
Both the north and southbound carriageways were closed between Junction 10 for the Black Country and 10a for the M54 from 9.30am
See tomorrow's Express & Star for an in-depth report.