Downton Abbeystar Michelle Dockery paid tribute to her late fiance John Dineen during his funeral on Wednesday, where the actress delivered a moving eulogy and sang a song that had been meaningful to the couple during their relationship.

"I was honored to know John. To love him and be loved by him," an emotional Dockery said during the memorial, according to the Irish Times. "He was my friend, my king, my hero, my everything. We celebrate him, we honor him and we will miss him."

WATCH: 'Downton Abbey' Star Michelle Dockery's Fiance John Dineen Dies of Cancer at 34

Dockery also sang the 1937 Oscar Hammerstein song "The Folks Who Live on the Hill," which the actress said she used to sing to Dineen, the Irish Independent reports.

Dineen, who died on Sunday after a battle with cancer, was laid to rest at St. James Church in Ballinora, Ireland. The funeral was held one day before Dineen would have turned 35. Dockery was by her fiance's side at Marymount Hospice, a facility close to his parent's home in Ireland, during the final days of his illness.

Dockery, 34, and Dineen, a London-based PR professional, got engaged earlier this year. The couple began dating in 2013 after being introduced by Dockery's Downton Abbey co-star Allen Leech.

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"Whether in his work or his personal life John was extremely loyal," Dockery shared with mourners during the service. "It was clear that when John was in your corner he was there."

A private cremation service was held following the memorial, which included traditional requiem mass.

For more on Dockery and Dineen's relationship, and his battle against cancer, check out the video below.