I would talk to somebody at PC about this, based on the 'tuk-tuks' and holy week comments, might as well be my former post. If you're reporting sexual assault they can't come down on you for breaking curfew/security rules, one of probably the only instances you get immunity, at least in Guatemala.

As you probably know, drinking is an issue with some volunteers, as that is sort of health related, they could legitimately refer you to the PCMO or somebody to work on this issue. Who knows what they put in drinks at whatever clubs you went to, but getting drunk and trying to deal with this situation can be dangerous.

It is good that these guys didn't get aggressive with you, I guess because your boyfriend and his cousins were there, but this could have ended differently and very poorly. There was a volunteer in Guatemala years ago who got drunk in Antigua and was stabbed around 1 or 3 am and almost bled to death. These guys could have stabbed you and the boyfriend, who knows, anything can happen in a situation like that.