United Kingdom, Feb. 15 -- Katie Thurston has been diagnosed with breast cancer.

The 34-year-old reality star - who got engaged to comedian Jeff Arcuri last September - took to social media on Saturday (15.02.25) to reveal that she is suffering from the disease and her Valentine's Day plans had been thwarted as she had to make logistical arrangements for her treatment.

She wrote on Instagram: "Life update: I have breast cancer.

"Yesterday I saw all the couples post their Valentine's Day celebrations. I felt envious if I'm being honest. Jeff took me to Hawaii and after, we were going to travel the world before planting roots together in NYC finally. But instead, my Vday was spent coordinating a place to live as I have to go back to LA f...