The mezzo-soprano told her Twitter followers in August that she "absolutely denied" any suggestion of a fling with the former England captain.
Her decision to acknowledge the rumours, which at that point were not heavily reported in the press, led to Max Clifford suggesting that Jenkins "maximised" publicity by responding to the gossip.
In an interview with Wales Online, Jenkins said: "From my point of view, I was actually getting months of people [bringing up the affair rumours] to me on Twitter and calling my friends and asking if it was true... it went from being now and again to constant abuse."
Previous reports suggested that Jenkins's Twitter denial led to her receiving death threats, but the singer has now said that the abuse had already begun by that point, revealing: "I was getting death threats before I spoke about it. You wouldn't believe how crazy and out of control it was getting."
Jenkins insisted that she stands by her decision, and also said that there is no rift between her and the Beckhams, claiming: "My PR people and their PR people spoke and everyone's happy with the way the situation's been handled.
"I still maintain I had to stand up and correct what people had been saying."
Watch Katherine Jenkins perform 'Angel' below: