It's best not to keep mentioning the care home to your mother as it is likely to make her more anxious and she might change her mind about going there. Just pack up a few things surreptitiously and take her there. You can always drop some more things off later. If she wants to know why she's going there just say that it's a convalescent home and she's going to stay there to build up her strength after being in hospital. There really is no point in telling her that she will be staying there for ever.