Ms Gowing's body has never been fully recovered, although remains were found at two rural locations near her home in Flintshire, North Wales, and near Chester.
Clive Sharp, 47, of no fixed address, pleaded guilty to her murder at Mold Crown Court last month.
Mr Justice Griffith Williams ordered that he serve a minimum 37 years behind bars before he can be considered for parole.
More top news
Parents of British man Nick Alexander killed in Paris attacks speak ahead of memorial service in French city.
Christian Hickey, seven, was shot on the doorstep of his home, now he is asking Santa to help police catch the people who hurt him.
A man accused of stabbing his father to death during a row over food has been arrested by police.