I would just define her as someone who will only be there on her terms.....& go off doing other things with other friends. If this person is nice, then I wouldn't mind getting together once in awhile if when it is convenient for her it also works for me. I wouldn't go out of my way to make it work. I can be friends with lots of different people....but it is more about having company to do something with IF the timing works. Most of us have very busy lives owning farms or working & living alone so life's priorities come first then socializing.

I tend to accept others on their terms because I tend to have my own at times too....though I do try to make time when they have time if possible.....because my life is usually very demanding & getting away can be nice.