Why do they do it?
You know those people who bail all the time to the extent that you can predict that they won't attend events and will let you down?
And why do mugs like me rely on people we know aren't reliable?
Yes, feeling sorry for myself. DH tells me I do too much for people for so little on return. Anyone else like this and fancy making a resolution to be more selfish (within reason!) from now on?!