IMO something did happen between she and your boyfriend during your last trip, but you don't know about it, and your boyfriend isn't telling.
Even one extremely terrifying experience can change an iguana permanently. But most recover in a matter of weeks to six months to a year of extremely patient human-to-iguana love flow. Perhaps a fierce visiting dog or cat who was yowling and scratching at the cage could do it, or being fed some drug or other, such as hallucinogenics could do it too. Even being taken outside into a crowd of people, like at a mall.
In all of my reading and personal experience, if an iguana has an adequate cage, and it seems yours does have that, they automatically view the habitat as their own private and safe territory, and can go inside or be put inside to calm down. It's a bit strange that your ig doesn't seem to feel that way.
My advice is sure to be what others have written. Keep interacting with her as much as she can tolerate, Be happy she's not stopped eating (which would lead to dehydration and vet visits and death), and protect her from strange things, like friends you invite over. When something is scheduled that to her might be stressful, first cover her habitat with as many blankets as it takes to block her view out. She won't like new sounds, but at least you can shield her from potentially scary sights. Even people they don't know are quite scary to many iguanas.
I'm hoping that she will gradually lose her intense stress, and eventually get back to normal. With her displaying such a strong reaction, anything that your room-mates may have done, they will probably avoid it in the future.
In http://www.anapsid.org/pdf/icfs.pdf there is an article titled "S-S-S-stress!!" that I think you should read to get more equipped to bring her back from the edge.
Please keep us posted. I'm very interested in what her future holds.