Mel Schilling -- the host of "Married at First Sight UK" -- has died.

Schilling's husband, Gareth Brisbane, announced the sad news in an Instagram post, writing she passed away peacefully Tuesday "surrounded by love."

The death follows a terminal cancer diagnosis, which Schilling revealed on March 12. At the time, Schilling said she had been battling the disease for about three years. She was diagnosed with colon cancer in 2023 and had it removed the following year ... but later "small nodules" were found in her lungs.

In his post honoring his late wife, Gareth wrote ... "In her final moments, when I thought cancer had taken away her ability to speak, she ushered me closer and whispered a message for Maddie and me that will sustain me for the rest of my life. It took all of her remaining strength ... Even then, her only thought was for Maddie and me.”

He continued ... “This is a woman who became a new mom and a TV star at 42 -- and nailed both. This is a woman who, through two years of chemotherapy, when she could barely lift her head from the pillow, never complained and never stopped showing courage, grace, compassion and empathy, and never missed a day of filming.”

Schilling and Gareth were married for 15 years and share a 10-year-old daughter, Madison.

Schilling was 54.

RIP