The 21-year-old singer took to Twitter once again to post her messages about her pet, who died last month, reported Daily Mirror.
Describing herself as his "mommy", the singer wrote a lengthy message saying she had been crying all day in bed, and did not think she would ever get over the guilt she felt.
"I keep asking why would the world take my sweet boy from me I'm just a baby myself... I depend on my mother still. She is the one at the end of the day I want to hold me when I'm sad, scared, lonely.
"Her one job in this world is to eel me out of harms way... I was Floyd's mommy. I don't know when the regret and the guilt will fade. I don't know if it ever will," she wrote.
Cyrus confirmed her dog's death on Twitter in April.