I have just pulled my daughter out of nursery. I just didn't see the point in making her stay in a room full of other kids, doing the stuff we do at home before we set off to do the things she was missing out on when she was at nursery.
Last week, every day was a morning of doing quiet activities so as to not tire her out, then trying to get her to nap and eat lunch in time, so I would have time to take her, crying, to nursery, so she could spend three hours in one room and I could go home and twiddle my thumbs while the baby napped, then she would come home grumpy with a sore tummy from eating the unlimited fruit they gave her and I would have a battle to get her ready for bed. For five days.
I'm looking at this weeks calendar now. We have swimming, messy playgroup, library, woodland nature hunt, day trip on the train, dancing lesson and another day trip in a big group of under 7s. We will surround those things with plenty of cooking, gardening, visiting friends and family, playing in the garden, puzzle books, board games and so on. I really don't think she is missing out in any way.
She used to go to nursery, when I worked and needed childcare, but I don't see why, if she has you at home, she needs to be left in a class of kids.
You are aware that school isn't compulsary either? If you don't think she is ready, HE until she is. I don't see why people are openminded about sahms/wohms when the kids are tiny, but the minute they turn five, their parents can't be trusted to know what is best for them.