Miley Cyrus says it 'makes me sick to my stomach' that same-sex couples who love each other cannot get married.

To show her support for LGBT equality, the Hannah Montana star got a tattoo last year which said: 'All LOVE is equal.'

She shared a photo of herself on Twitter and the backlash was instant.

'A lot of people mocked me,' Cyrus writes in the new issue of Glamour. 'They said, 'What happened to you? You used to be a Christian girl!' And I said, 'Well, if you were a true Christian, you would have your facts straight. Christianity is about love.'

The 19-year-old singer and actress writes that the debate resulted in a lot of threats and hate mail.

'At one point I had to say, 'Dude, everyone lay off,'' she writes. 'Can't people have friendly debates about sensitive topics without it turning into unnecessary threats?'

Cyrus, who will star in the comedy So Undercover this summer, has not let the backlash silence her.

'We all should be tolerant of one another and embrace our differences,' she writes. 'My dad [country singer Billy Ray Cyrus], who 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.'