Can I get money back if given to someone that I was not on a lease with but intended to live with them but then decided not to.

Tough to get back, bc she has the money.  And if she changed her position, based on the fact that she took a two bedroom apartment instead of a one, then you could be held liable. If there is no chnage in her position, as in she has this huge house, and took deposit from you, still, if she was counting on you, and did not take someone else, lost money waiting for a new room mate.  Tough