MIAMI -

"This is not easy for either family and we cannot explain it. Only God can explain it," said Derek Ian Medina, the father of 31-year-old Derek Medina, who police say killed his wife then posted an apparent confession and picture of her body on Facebook.

Police arrested Derek Medina, 31, on Thursday after he admitted to killing his wife, Jennifer Alfonso, inside their South Miami home, according to an arrest affidavit.

The photo Medina posted showed a woman wearing black leotards with her knees bent backwards. Blood covered her left cheek and arm. He tagged the photo as Alfonso and captioned it "RIP."

Derek Medina Facebook post

Medina made his first court appearance Friday after he was charged with first-degree murder. A judge ordered he be held on no bond.

His father, Derek Ian Medina, said he knew about his son's struggling marriage. Records show the couple married, divorced, then remarried about three months ago.

"They had a very rough relationship when they were married. He was always scared of her. He reported to me she always beat him up," said the suspect's father. "As a man, he didn't want to tell too many people because as a manly thing."

He's not that type," added Valerie Medina, the suspect's aunt. "He's not the type to fight and be like that."

Medina graduated from Coral Gables High School. He served as an altar boy at the Episcopal church on the University of Miami campus.

The 31-year-old also wrote a series of e-books with long titles that dealt with relationships and his experience with aliens.

Derek Medina's self-published books

Published On: Aug 09 2013 11:31:26 AM EDT
Medina maintained website called EmotionalWriter.com

Derek Medina published his own self-help books and maintained a website called EmotionalWriter.com.

Book1
1 / 7

World Just Ask Yourself Why We Are Living a Life Full of Lies and How I am Emotional Writer Made All of My Professional Dreams Come True Blocking Society's Teachings

Alfonso's family heartbroken

"Everyone is doing okay," said Rohan Knox, Alfonso's stepfather. "They're still coping. All I can say is that we're trying to remember all the happiness about her."

Earlier in the week, Alfonso spent the day with her daughter, mother, and stepfather.

"She was always happy and always smiling and that's what we're trying to do right now," said Knox. "Just think about those happy moments."

Knox said Alfonso was a spirited woman who loved her daughter. Friends called her relationship with Medina troubled.

Knox added that the family can't believe her daughter's death was so public.

"Someone has to be strong and I'm holding my own with them and it's just rough for the girls," he said. "For her (Alfonso's mother), it's just rough, but like I said, somebody has to be strong."

"I hope that God can forgive you (Medina) because I can't," said Daysi Fernandez, who worked with Alfonso at Denny's.