Glad it's all sorted out!!
I had a similar experience when I was in London for a weekend recently because I have a friend just like this.
I don't know what the answer is, because if I came out and said something like "look, if you are too busy just let me know now and I'll arrange to meet up with Gemma instead" she'd take it as a criticism and back off from me. And I do value her friendship because she is very funny and always good company when you do pin her down.
But at the same time, I have other friends and I value them too, and I was only in London for a few nights!!!
I suppose I can't force people to respect my time and my other friendships.
So, how do you deal with a friend like this?!? What's hte answer or can they not be managed? Is it put up and shut up or lose the friend?