Success!! I can hardly believe it. I didn't want to post sooner in case it was an abberation, but my LO has now taken a bottle for one feed for 4 days in a row.
I decided just to think about what my LO would like most and combined that with some things I'd read and heard, and it worked! I decided that I would try to give her the bottle, rather than my mother, who is going to care for her some of the time when I go back to work. I got a cloth that smelled of my milk and draped that over my shoulder. I looked at all the bottles and teats I had and chose one that had a small narrow long teat - a Dr Brown's, first size. I made sure the teat was really warm, and the milk, which someone here had suggested.
And I just snuggled her in my arms in her usual feeding position and she took the bottle. She protested a tiny bit, but when she tasted the milk, she was fine. ( I am giving her goat's milk formula, Nannycare, in case anyone is interested. Supposed to be much better for their digestion than cow's milk based formula.)
After the first two days, mum gave her the bottle, and she was fine with that too. So I think we are on our way.
Thanks for the advice. Hopefully this will also help others with the same problem.