Von D, a tattoo artist-turned-reality star, tweeted that the relationship was over and that "cheating on your loved one is the most hurtful thing one could do."
Cheating on your loved one is the most hurtful thing one could do. I hate to have to admit, that this relationship is indeed over.— Kat Von D (@thekatvond) June 26, 2013
But Zimmerman, the music producer who performs under the name Deadmau5, wrote on Facebook that he was "not, at any point, unfaithful to Kat during our time together."
Zimmerman also said he had slept with another woman while he and Von D had been separated, before their engagement, and that she knew all about it. He said the split was mutual.
"At the end of June, it was clear that the relationship was not working and we mutually ended the engagement," he wrote.
The couple had planned to wed in August.