According to the Daily Mail Online, he had been caught cheating on her in their own home in Wellington, Florida by her security team.
Miranda shared his thoughts with Brazilian magazine Epoca following the scandal.
“I am really in the midst of a storm,” he said. “But I will not give up on my love.”
He continues saying that “it won’t be easy but [he] will fight until the end.”
An unnamed member of the international show jumping circuit told the DM Online that the affair was “nothing serious” despite rumours that it had been going on “for about a month.”
Despite the mess that is unfolding in her personal life, Onassis, who is also an equestrian, has an interest in representing Greece in the Rio Olympic Games.