Demi Lovato's Father's Funeral Was 'The Hardest Thing' She's Ever Gone Through

Demi Lovato is still coming to terms with the death of her dad, Patrick Lovato, who died last weekend at the age of 54 after his battle with cancer.

Although Lovato had been estranged from her biological father since 2007, the "X Factor" mentor took to Twitter to open up about her devastating loss this week, telling her followers, "I feel so humbled to have had so much support from my fans, friends, family and complete strangers.. God bless you all, thank you so much."

Lovato posted another message following her father's funeral on Saturday.

Lovato was raised by her mother Dianna De La Garza and her stepfather, Eddie De La Garza. The 20-year-old has previously opened up about her strained relationship with Patrick, who split from her mother in 1994. In a 2011 song entitled, "For the Love of a Daughter," Lovato sings about her father's alcohol-related issues, which obviously took a toll on her.

"You try to have faith in somebody, even when you're the last person that believes in him," Lovato told the Daily News of Patrick in 2009. "But when somebody lets you down after you've been the only one there for them, and so many times, you don't know what to do."