But the true author has now come forward - Tom MacMaster, an American man studying in Scotland.
Many Syrian activists have reacted angrily, accusing him of trivialising or even harming their cause.
"One day if I'm kidnapped by my government, many readers won't care because I could turn out to be another Amina," wrote one Lebanese blogger.
The Gay Girl in Damascus blog, dating back to February this year, claimed to document the life of 25-year-old Amina Abdallah Arraf al-Omari, a half-Syrian, half American lesbian living in Damascus.
Entries covered her social life and relationships, but "Amina" also criticised President Bashar al-Assad and spoke about her role in the growing anti-government protests.
"What a time to be in Syria! What a time to be an Arab! What a time to be alive!" read an entry on 24 March.
"I want to rush out in the street and celebrate (and will as soon as I finish writing this)."
Read more: bbc