Hmm... Are you are getting married in canada? (sounds like it) That could be a problem.
If you get married in the United States, she could say here, but could not work. She would have to file to be able to work (which takes 3 months to get) and then file travel papers so you can leave the country. Once you are married though in the US you I am 99%sure she can stay in the country.
Once you get married in the US, you can file for everything at once (I-485, I-864, I-765, I-131, I-130, I693).
It is a pain in the ass. We are doing it without a lawyer.
There are "kits" you can get online that walk you through it also.
Maybe you could fly to vegas and get married again there and she could stay in the country.