Ryan Main, 32, repeatedly put the woman through a horror ordeal at a flat in Glasgow’s Cranhill.
She was found naked by police before bravely revealing how she had suffered.
Main ended up on remanded in HMP Barlinnie – but continued to hound the woman for more than a year in a series of threatening letters.
In one, he stated: “Do not give evidence or go to court. I have people ready to do what I say.
“I will make your life a misery before I burn you out of your gaff.”
Main was sentenced as he returned to the High Court in Glasgow.