'My boyfriend and I had sex hours after he had strangled a woman to death'

It was normal for Heather’s cabbie boyfriend Christopher Halliwell to work late on a Friday.

At 1.30am one March night in 2011 he messaged her to say: “I love you,” before she went to bed.

Heather Widdowson found out much later that an hour after writing it he abducted and murdered 22-year-old Sian O’Callaghan after getting into his taxi to leave a nightclub in Swindon.

Her body was found in Uffington, Oxfordshire, five days after he strangeld her to death on March 19, 2011.

And it wasn’t his first killing. Halliwell had also abducted and murdered Becky Godden, 20, who had working as a prostitute when she disappeared from Swindon in 2003.

The morning after murdering Ms O'Callaghan, Halliwell got up early to take his taxi to the car wash, ex-girlfriend Heather remembered.

That afternoon he was in good humour, “laughing and joking” as the couple ended up in bed.

As she made love to her boyfriend, Heather had no idea he’d spent the morning scrubbing Sian’s blood from his car seats.

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Heather met Halliwell in 2003 and they moved in together, in Swindon, two years later. She recalled: “We had a happy and loving relationship. We both worked odd shift patterns and tried to make time for each other.”

Five days after the killing Halliwell was arrested and confessed to the murder of Miss O'Callaghan, a 22-year-old office administrator. He also agreed to show police where he had hidden her body - at a remote beauty spot, close to the Uffington White Horse in Oxfordshire.

Then, he shocked officers by telling them he had also murdered Miss Godden, eight years earlier.. The confession led officers to her remains in Eastleach, Gloucestershire, two days later.

Heather said: “In all the years I was with Chris he was hiding this sick secret. I wonder if I ever really knew him.”

In October 2012 Halliwell was sentenced to life with a minimum of 25 years for murdering Sian O’Callaghan.

In September 2016 he was found guilty of murdering Becky Godden-Edwards and given a whole life sentence. Heather said: “I’ve no feelings for him now. He is a cold, callous coward. I’ll never forgive him.”