Scandals pop up within royal families around the globe from time to time, but one of the most prevalent ones in recent years has been that of Spain's former King Juan Carlos.

The monarch, now 82, was caught up in a number of controversies largely centered around his reported affair with Danish businesswoman Corinna zu Sayn-Wittgenstein.

Now 56, zu Sayn-Wittgenstein spoke with the BBC about her time with the king, how it came to an end and what transpired in between.

EX-SPANISH KING JUAN CARLOS IN UAE AMID GROWING FINANCIAL SCANDAL, ROYAL OFFICIALS CONFIRM

Juan Carlos and zu Sayn-Wittgenstein met in February of 2004 at a shooting party, where she impressed the king with her knowledge of firearms.

Corinna zu Sayn-Wittgenstein, the former mistress of Spain's former King Juan Carlos. (Photo by JP Yim/Getty Images of Opera Italiana Is In The Air)

Corinna zu Sayn-Wittgenstein, the former mistress of Spain's former King Juan Carlos. (Photo by JP Yim/Getty Images of Opera Italiana Is In The Air)

After a few months of speaking on the phone, they went on a date in the early summer of that year.

The monarch is married to Queen Sofia.

"We always laughed a lot. We immediately clicked on many things, and we had many common interests — politics, history, fantastic food, wines," recounted zu Sayn-Wittgenstein to the BBC. "I was living in London at the time, having just started my own consultancy business. And I was a single mother of two. So we would meet in Madrid in a small cottage on the larger estate, and we traveled together."

Despite Juan Carlos having a busy schedule, his former lover said he'd "phone me up to 10 times a day."

"I mean, it was an immediately very strong, deep and meaningful relationship," she explained.

SPAIN'S EX-KING LEAVING COUNTRY AMID ALLEGATIONS OF FINANCIAL MISCONDUCT

Zu Sayn-Wittgenstein said she brought up Sofia and asked how she would feel about the affair.

"He said they had an arrangement to represent the crown, but they led totally different separate lives," she explained. "And the king had just come out of a nearly 20-year relationship with another lady who also had a very important place in his heart and in his life."

In 2009, a proposal happened.

King Juan Carlos abdicated the Spanish throne in 2014. (Photo by Daniel Perez/Getty Images)

King Juan Carlos abdicated the Spanish throne in 2014. (Photo by Daniel Perez/Getty Images)

"... I was very much in love with him, but I foresaw -- I'm a political strategist -- that this would be very difficult. And I thought it might destabilize the monarchy," zu Sayn-Wittgenstein recalled. "That's why I never really encouraged it -- I just took it as a token of the seriousness of the relationship, rather than something that would actually materialize."

The relationship took a turn and ended that same year. However, the two remained close, in part because the king was close to zu Sayn-Wittgenstein's kids.

SPAIN'S JUAN CARLOS PRESIDES OVER LAST MILITARY PARADE AS KING

Later in 2009, Juan Carlos asked to see zu Sayn-Wittgenstein and told her that a tumor had been discovered on his lungs. While doctors would eventually deem it benign, the former mistress spent time at the king's side during his treatment.

Former King of Spain, Juan Carlos of Spain and his wife, Sofia. (Photo by Juanjo Martín - Pool/Getty Images)

Former King of Spain, Juan Carlos of Spain and his wife, Sofia. (Photo by Juanjo Martín - Pool/Getty Images)

In 2012, she accompanied the monarch on a trip to Botswana, a hunting trip that served as a birthday present from Juan Carlos to zu Sayn-Wittgenstein's then-1-year-old son.

PRINCE ANDREW WILL RECEIVE ROYAL HONOR ON HIS BIRTHDAY DESPITE EPSTEIN SCANDAL

During the trip, the king shot and killed an elephant before fracturing his hip, resulting in an emergency reparation — and exposing the affair.

As soon as they arrived in Spain, zu Sayn-Wittgenstein said she was being watched.

Spanish King Juan Carlos of Spain (L) and Corinna zu Sayn-Wittgenstein attend the Laureus Sports Awards 2006 at Parc del Forum on May 22, 2006, in Barcelona, Spain. (Photo by Carlos Alvarez/Getty Images)

Spanish King Juan Carlos of Spain (L) and Corinna zu Sayn-Wittgenstein attend the Laureus Sports Awards 2006 at Parc del Forum on May 22, 2006, in Barcelona, Spain. (Photo by Carlos Alvarez/Getty Images)

"This was the beginning of a campaign to paint me as this Wallis Simpson, Lady Macbeth, evil character who'd led this wonderful man astray on this trip during a big economic crisis," she claimed to the BBC.

She even alleged she was surveilled by Spain's intelligence service, the Centro Internacional de Inteligencia (CNI), which allegedly targeted her apartment in Monaco.

"The apartment was occupied when I was traveling," she recalled. "I suddenly received messages from a security company saying, 'We've been contacted by your friends in Spain.' And I was texting the king, saying: 'Who are those people, what's going on?' He told me they were there to protect me from the paparazzi."

Zu Sayn-Wittgenstein added: "But had he been concerned about my security, he could have called his close friend, Prince Albert [of Monaco], who's also a longstanding friend of mine, and said, 'We have some security concerns — could you keep an eye on Corinna's flat?'"

MEGHAN MARKLE, PRINCE HARRY BELIEVE SANTA BARBARA IS THEIR PERMANENT HOME AFTER 'TURBULENT' TIME: REPORT

Although she's unaware of what exactly they were looking for, zu Sayn-Wittgenstein claimed the intruders were searching for "documents."

While on a business trip to Brazil, zu Sayn-Wittgenstein said she received anonymous death threats hinting at tunnels between Monaco and Nice, according to the BBC, saying it was likely a reference to the death of Princess Diana.

She also claimed that she found a book about Diana's death in her Swiss apartment.

Corinna zu Sayn-Wittgenstein (left) and former King Juan Carlos carried out an affair for many years and were even engaged.

Corinna zu Sayn-Wittgenstein (left) and former King Juan Carlos carried out an affair for many years and were even engaged. (Getty/AP)

In 2014, Juan Carlos abdicated the throne and remained busy with official engagements. That same year, the king "made desperate attempts" to reconcile their relationship, zu Sayn-Wittgenstein said.

"At some point, he realized I wasn't going to return, and he went completely ballistic. He asked for everything back," she said of the around €65 million (about $77.1 million) he gave her, which is now under Swiss investigation."

She continued: "I think it was just a tantrum he threw. So he's confirmed to the Swiss proceedings that he actually never asked for the money back and that I never carried money on his behalf."

Former King of Spain Juan Carlos (right) with his son Felipe, who is now the king. (Photo by Fernando Alvarado-Pool/Getty Images)

Former King of Spain Juan Carlos (right) with his son Felipe, who is now the king. (Photo by Fernando Alvarado-Pool/Getty Images)

Of course, the transfer has caused a stir, and she said the harassment has "intensified."

Despite finding herself in a unique position these days, zu Sayn-Wittgenstein said she looks back on her relationship happily.

CLICK HERE TO GET THE FOX NEWS APP

"I do not regret at all my romantic relationship with Juan Carlos," she told the BBC. "I have very sincere feelings for him. And I am extremely saddened by the turn it has taken."