Snowy1 Whilst I can see that you have difficulties in your life that put extra pressure on you, like your other half's illness, I'm not sure that being told an earlier time would resolve the issue. If you are extremely busy, stressed out and forgetful, surely it wouldn't make much difference if you're told an earlier time? The same issues - being overstretched and consequently losing keys, etc. - would still be there whatever time you are aiming for? Is it perhaps that because you're busy you try to do more things than you've got time to do, and miscalculate about how much time is left to get ready/travel somewhere? I have done that a couple of times myself and it's easily done but now I make a conscious effort not to try to squeeze in too much before going out.
It is a little inconsiderate to consistently turn up late (I think it's plain rude to consistently turn up very late) and there are circumstances where I wouldn't be happy if that happened - meeting in a pub I'm not familiar with, for instance. But there are worse things people can do I have one friend who does tend to turn up quite late and it is a little annoying, but because she is a good friend in other respects, I don't make a fuss about it.
(and I agree with annifrance - people turning up early for a meal can be a great deal more stressful than them turning up late).
I must say I'm surprised that some Gransnetters are getting so snippy with each other over this relatively minor issue.