Am I Loosing Being Patient & More than Fair?

I know I've posted about the kids and my babysitting sagas. Well, I've hit my limit with the mom. I don't get the common courtesy of being told when she doesn't need me 95% of the time. Yesterday was a perfect example.

I'm all set to watch the kids. Even ready to go before they get off hte bus. Have I been told that the mom's boyfriend is now watching them on Thursdays? No. Not at all. Not even given an indication. I find out by going up to the car and the mom ("J") rolling down her window and asking me if I wanted a ride down to the shop. Today when I'm talking to her mom, her mom mentions something about the kids being busy this weekend. THat I might want to call "J." I've called "J" and left her a message knowing I won't hear from her before I leave for knitting in the morning even though I said in the message it's ok to call me when she gets out of work and wake me up.

I've hit the point that I'm going to tell "J: that I'm going to go on in my life and make plans. If she needs me, to give me 24 hours notice minimum and I'll watch the kids unless it's a weekend I'm going to my parents. On those weeks though I will make sure I have other arrangements set up though. Am I being fair? This happens so many times, me not getting the courtesy of being told. Or am I just being a frustrated person.