Kimberly Guilfoyle wished her ex-fiancé Donald Trump Jr. a happy birthday as he flaunted his new relationship with Bettina Anderson at his father’s New Year’s Eve party.

Guilfoyle, 55, shared a heartfelt birthday social post for the president-elect’s son, who she dated for several years.

The news personality and ex-wife to California Gov. Gavin Newsom shared a collage featuring pictures of her and Don Jr. smiling together, demonstrating their amicable break-up.

The pair got together in 2018 after Don Jr. divorced his now ex-wife Vanessa. They were engaged in 2022.

Since then, Guilfoyle has become a prominent member of soon-to-be president Trump’s circle. She was recently made Trump’s ambassador to Greece.

But trouble publicly arose after Don Jr. was caught kissing Anderson during a romantic dinner in Palm Beach about three months ago – before he’d announced his split with Guilfoyle.

Guilfoyle was reportedly ‘blindsided’ by the photos of Don Jr. and the glamorous model.

Friends of the former prosecutor exclusively told DailyMail.com that Guilfoyle was completely caught off guard when she learned about Anderson and her fiance at the time.

Kim Guilfoyle wished Donald Trump Jr. a happy birthday in a heartfelt Instagram story post

Don Jr. and Bettina Anderson were seen smiling on their way inside Donald Trump’s New Year’s Eve party

Guilfoyle’s post comes after the pair amicably broke off their engagement

The insider said: ‘Kimberly either didn’t know about Bettina – or didn’t want to know. Did she hear whispers that Don Jr. was fooling around with someone else? Probably.

‘She’s no fool but it’s easy to deceive yourself when you’re so committed to someone and believe he’s committed to you.’

Rumors of the relationship only intensified after a photo of them holding hands during a night out in Palm Springs in December.

Days later, he finally addressed his split from Guilfoyle in a statement to Page Six.

‘Kimberly and I will never stop caring for each other and will always keep a special bond,’ he told the outlet.

‘I could not be more proud of her and the important role she’ll continue to play [as US ambassador to Greece].’

Don Jr. celebrated his 47th birthday at his father’s annual New Year’s Eve bash at Mar-a-Lago, publicly debuting his new socialite girlfriend just weeks after he announced the end of his engagement to Guilfoyle.

The pair strutted down the red carpet into the famous Florida club flashing bright smiles.

Meet Kimberly Guilfoyle, Trump’s new pick for ambassador to Greece

Anderson, a model and socialite, has caused a stir among some Trump supporters who claimed she is not ‘MAGA’ enough

Rumors about Don Jr. and Anderson’s relationship spawned when the couple started going out together months before Don Jr. addressed that he was no longer engaged

Bettina Anderson seen with Don Trump Jr and ex-wife at party

Don Jr. and Anderson, 38, rang in the New Year alongside other prominent members of Trump’s group, including ‘First Buddy’ Elon Musk and Vice President-elect JD Vance.

Anderson has been slammed as a ‘social climber’ and a Florida party girl. But she appeared to subtly responded to critics by citing a bible verse in a social media post in late December.

‘So let them lie. Let them manipulate. Let them talk. You just be still, because when God is on your side, who can stand against you?’ the bible passage, from the book of Exodus, states.

Friends of the president elect’s eldest son have expressed concern that his new love interest is not ‘MAGA enough,’ based on her social media posts and political stances.

For example, during the COVID-19 pandemic she shared an image of her wearing a mask posing alongside a sign that read: ‘Only you can stop the spread of ignorance.’

Some even accused her of being a ‘liability’ to Trump’s administration and using her relationship with Don Jr. for fame.