State Department initially denied her request to attend Equality Forum in Philadelphia
The measure failed by a 51-17 vote margin
Same-sex marriage bill received final approval on April 17.
"Mariage pour tous" bill passed by 331-225 vote margin
Six activists took part in State Department-sponsored trip
Advocates claim rhetoric against bill has sparked anti-gay violence
Gays and lesbians can begin to marry in August
Parliament vote to take place
79 percent of 100 members supported recommendation, 2014 referendum possible
Measure returns to the National Assembly next week for a final vote