I can see where you ae coming from. If a girl did that to me I would wonder if she was just mucking about, playing some kind of game. Maybe I am too suspicious. But I have been hurt too many times to want to be caught out by a girl or to appear weak to a girl now. There are some girls who seem to muck people around, I don't know why they do it maybe some kind of mind game or test. I'm not into them. If I were you I would do as suggested and ask her calmy why she keeps cancelling. Explain how it is not fair on you, how it is an inconvience to your planning of your social life the way she keeps cancelling. If she has a good reason meet her, but make it clear you are not going to put up with with further cancellations in a tactful kind of way. If I knew quite how to do that I would say, but you need to be firm but fair. Text messages can be a pain sometimes, they are such an easy get out tool when someone wants to cancel an arangement!