Liam Payne and girlfriend Kate Cassidy had planned to get married before tragic death

In a heartfelt statement posted to Instagram, Kate Cassidy said that the couple had recently envisioned their future together, including marriage and a life shared "forever."

The former One Direction star died at the age of 31 in Buenos Aires, Argentina, after falling from a third-floor balcony at the Casa Sur hotel.

Cassidy wrote: "I don’t even know where to begin...My heart is shattered in ways I can’t put into words." She described Payne as "the love of my life," noting his contagious energy and the joy he brought to the lives of millions of fans, family, and friends.

The American social media influencer added: "You brought so much happiness and positivity to everyone - you are so incredibly loved.” Cassidy also recounted a recent moment when the couple sat outside, talking about their dreams and their future together.

She said: "A few weeks ago, we sat outside on a beautiful evening manifesting our lives together. I keep your note close, even though you told me not to look at it. It said, 'Me and Kate to marry within a year/engaged & together forever 444.'"

"I wish you could see the huge impact you've had on the world, even as it feels so dark right now. You brought so much happiness and positivity to everyone - millions of fans, your family, friends, and especially me. You are so incredibly loved.

"You are - because I can't say were - my best friend, the love of my life, and everyone you touched felt just as special as I did. Your energy was contagious, lighting up every room you walked into.

"None of this feels real, and I can't wrap my head around this new reality of not having you here. I'm struggling to figure out how to live in a world without you by my side. Together, we got to be kids again, always finding joy in the smallest things."

"Liam, you had the kindest soul and the most fun-loving spirit. It feels like I've lost the best part of myself. I can't imagine a day without your laughter and love. You brought so much light into my life."

The tribute also conveyed Cassidy's ongoing love for Payne and her promise to carry their shared dreams with her. "I will love you for the rest of my life and beyond, carrying our dreams and memories with me everywhere I go," she concluded, signing off as "Forever yours, Katelyn."

The couple had been in a relationship for two years and Cassidy reportedly returned home two days after his death.