Guyana's first Pride parade took place on June 2
Alexa Hoffmann said ex-roommate slashed her on Feb. 18
Violence, discrimination remain pervasive in the region
Discrimination, hate crimes persist in both nations
Gathering began a month after Pulse nightclub massacre
Life expectancy for trans women in El Salvador less than 35 years
Advocates protested government officials during opening plenary
Violence, discrimination, poverty among topics discussed