I live in Sweden as well and basically the same thing has happened to me and many people I've met. This is the first time I've experienced so many companies offering short term contracts and I really think it causes problems especially for foreigners (not sure if you are or not).

Unfortunately theres not much she can do outside of what her contract stated. Was there a notice period where she needs for example 2 weeks notices before being fired? Im sure if you go through the right channels, they could help or at least confirm that she can't be sent home. But of course it depends on the contract.

As for the future, I used to say be sure to only sign permanent contracts because where I'm from that's all that exists (or not even that just "work until you quit or get let go"). But now I see in Sweden that that's easier said than done. Employers are stingy with permanent contracts because then it's much harder to fire the employee. But know that eventually, after you've been wth the company a certain about of time they're required to offer you a permanent contract unless you're working as a contractor.

The next thing is once she gets job, I highly suggest getting unemployment insurance through arbetsformedlingen. You can read more about it here. http://www.thenewbieguide.se/work/labour-legislation/unemployment-insurance/. I think my sambo pays like 100kr a month for it and if he's fired he'll have his salary paid for up to one year.

Anyways, so that happened to her. Sweden is rough unless you have that permanent contract so good luck to her in future! Coming from a place that rarely does contracts for work, I'm still figuring it all out myself.