The former Hollyoaks actress called off her engagement to the Britain's Got Talent martial arts star last month, according to The Sun.
It was only confirmed in April that the couple were engaged. He proposed last year after dating her for three years.
However, their wedding is now said to have been cancelled and Atkinson is thought to have moved out of their Sheffield flat and returned to Manchester.
The split was reportedly mutual and no-one else was involved, with the pair simply growing apart.
Atkinson is best known for playing Lisa Hunter in Hollyoaks. She has also appeared on I'm a Celebrity... Get Me Out of Here! and Casualty.
Richards made it to the final of the second series of Britain's Got Talent as part of martial arts duo Strike, eventually losing out to dancer George Sampson.
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