I can't really speak on who should have the funds (you or her) because I don't have experience with that--nor the new landing cards, I guess (since I don't remember those questions on the card, but October 2008 was the last time I filled one out). But, I would ask you to reconsider only having a one-way ticket--that can sometimes raise a red flag for the IO, especially when you're asking to be let in for six months in one stretch. It can sometimes cause them to be suspicious (not all the time of course) and you might run into some trouble on that front.
Do you have a job to go back to in the US? School? A housing agreement, or some other binding contract? These would all go in your favor when you present yourself to immigration on the ground, since you're asking to stay for such a considerable amount of time with no return ticket.
*Some* people have had their sponsor write a letter detailing that they'll make sure the USC is taken care of financially and will have a place to stay and such, but I personally can't speak on whether or not this would work since I've never done it before.