I’m having some trouble with my sister that I don’t know how to deal with. Basically, she’s a huge flake. Often when we make plans to spend time together, she’ll change her plans and not tell me until the last minute (when or after we were supposed to meet) and sometimes not at all. She seems to do this with everyone and doesn’t understand when people get pissed at her for it. A few times she has claimed that she’s on her way home and then doesn’t show up and doesn’t answer her phone, which of course means we get worried. Later she’s admitted that she lied about being on her way to begin with.
I’ve tried to explain that this is really annoying for me and I’ve asked her to at least contact me and cancel ahead of time so I can make other plans. I’ve also asked her not to make plans with me if she doesn’t think she’ll actually make it. I get that sometimes things come up or take longer than expected, but this happens all the time. When I’ve tried to talk to her, she’s been pretty defensive about it and she hasn’t changed her behavior. She’s 19, which I think is too old for this kind of behavior.
I really enjoy spending time with my sister and I don’t want to stop doing that, but I also want her to be respectful of my time. What can I do?