American equestrienne Lauren Hough, who has reportedly set up home with Princess Anne's ex husband, was questioned during a show-jumping competition in San Diego.
She was asked if she was surprised by the controversy over her romance with Captain Phillips – 28 years her senior – who is divorcing his second wife to be with her.
She replied: "Not really, I guess I knew it was coming."
Asked if it had been a big decision to publicly confirm it, she said: "It was inevitable."
Lauren declined to comment on reports the couple had bought a house together in Florida or suggestions Captain Mark should resign his role of trainer of the US eventing team.
She did, however, say she had the full support of her teammates.
Zara Phillips' father is the Chef d'Equipe of the US eventing team and Lauren is one of his coaching assistants.
But she reportedly took up the position after their relationship began – something that has drawn criticism from those on the eventing circuit.
It was confirmed on Thursday that Captain Mark, 58, is divorcing Sandy – his wife of 15 years (pictured above with her husband) – with whom he has a 14-year-old daughter.
"Captain and Mrs Mark Phillips are separating and divorce proceedings have commenced," reads a statement from the pair's lawyers.
"The couple have a daughter, aged 14, and the care and support of her is Capt Phillips’s main concern at this sensitive time.
"Capt Phillips therefore requests that all parties respect their privacy in the months ahead."