Widespread media reports in recent months matched the red-headed grandson of the Queen with 25-year-old Florence Brudenell-Bruce.
However the pairing has ended and it was her decision, the Sunday Mirror newspaper reports, contradicting previous comments from royal sources that it was the prince who called it off.
"She felt he had a wandering eye all the time and she wasn't really into not knowing who he was flirting with or talking to when they were apart," a friend of Ms Brudenell-Bruce, nicknamed Flee, told the tabloid.
"So she ended it. She didn't want to carry on in a relationship that wasn't going to go anywhere.
"They both enjoyed themselves but Flee wasn't interested in taking things further."
According to the friend, the last straw came for Ms Brudenell-Bruce at a music festival where she saw Harry "flirting" with another pretty blonde.
"Flee saw he was chatting to her and got very jealous and disappointed."
The pair remain pals, the friend said.
