Susan Waring, 45, from Darwen, was last seen on January 29, 2019.
Alan Edwards, 48, of Blackburn Road, Darwen was later convicted of her murder and jailed for a minimum of 27 years.
The third anniversary of Susan's disappearance is tomorrow (Saturday, January 29) and police have issued a renewed appeal to find her body.
Det Chief Insp Lukmaan Mulla, of Lancashire Police, said: "Her murder remains one of the most difficult and heart-breaking investigations I have dealt with.
"Susan, so vulnerable, was subjected to horrific abuse by Alan Edwards, tragically ending in her murder.
"While her family has received justice with Edwards now serving a life term in prison, their suffering continues while her body remains missing.
"Edwards continues to deny Susan's murder and as such, is not revealing where he disposed of her body."
"I want to make a direct plea today to anyone with information about her disappearance to come forward."
Susan was subjected to several assaults by Edwards during their two-month relationship.
Two weeks before her disappearance, Edwards was seen punching Susan in the face on January 15, 2019.
She attended a doctor's appointment the following day with multiple injuries, including bruising and severe swelling to the face.
Accompanied by Edwards, she was advised to seek medical attention at a hospital but sadly, she never did.
Susan was last seen on Tuesday, January 29, 2019, in company with Edwards at Asda in Darwen.
Susan's family later reported her missing to the police, with police later launching a murder investigation.
"I believe someone out there knows where Susan's body is and can help police," Det Chief Insp Mulla added.
"I must stress, any information, no matter how seemingly small, could help our team to find her.
"Any calls to police will be treated in the strictest confidence."
"We want to find Susan and give her family some closure.
"Susan's death, the subsequent investigation and trial has left them devastated."
Anyone with information is asked to call 101, quoting incident reference number 0496 of January 27.
Alternatively, independent charity Crimestoppers can be contacted anonymously on 0800 555 111 or online at crimestoppers-uk.org.
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