I think she probably just needs time to calm down. No one likes finding out they've been lied to. Just like you have to take care of yourself so does she. I think her saying that she can't talk to you anymore tonight is a good boundary. She was letting you know that she couldn't handle anymore tonight. That doesn't necessarily mean she doesn't want to be your friend or help you it just means she had all she could take.

I think it's wonderful that you have a friend who cares enough about you to help support you and worry about your best interest. I also think it's wonderful that she respects herself enough to take care of her as well. Think about it, if she's overloaded she not only cannot take care of herself but can't help you either.