Was i mean to my friend?

okay, so i have to look for an apartment off-campus. Friend A is on the wait-list to be an RA. So I decided to room with Friend B. Now Friend A has been begging me to room with her, and saying that she won't take the RA position even if she gets it. But honestly, I can't afford to risk having an empty room in the apartment if she bails on me. So i finally had to explain it that my parents are MAKING me get a 2-bedroom apartment and that i can't do a 3-bedroom with her. Friend A now seems pissed and angry with me. What else could I have done? Honestly, I can't risk having her move out, and then getting a random awful roommate. Plus, the girl has been very bossy through this whole thing, which has deterred me from wanting her as a roommate even more. Thoughts?