The 'Who Owns My Heart?' singer unveiled the equality symbol inked on her finger in August 2011.
In a column written for Glamour, Cyrus once again spoke out in support of equal rights for gays and lesbians.
"Imagine finding someone you love more than anything in the world, who you would risk your life for but couldn't marry. And you couldn't have that special day the way your friends do - you know, wear the ring on your finger and have it mean the same thing as everybody else. Just put yourself in that person's shoes. It makes me feel sick to my stomach," she wrote.
"I believe every American should be allowed the same rights and civil liberties. Without legalised same-sex marriage, most of the time you cannot share the same health benefits, you are not considered next of kin and you are not granted the same securities as a heterosexual couple.
"How is this different than having someone sit in the back of the bus because of their skin colour?"
Cyrus went on to say that even her father Billy Ray Cyrus supports gay marriage despite his conservative values.
"We all should be tolerant of one another and embrace our differences. My dad is a real man's man, lives on the farm and is as Southern and straight as they come. He loves my gay friends and even supports same-sex marriage. If my father can do it, anyone can," she explained.
"This is America, the nation of dreams. We're so proud of that. And yet certain people are excluded. It's just not right."
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