I would take the hard line and get her a Groclock, explain that mummies and daddies need sleep and when she can see the moon on the clock, that means mummy and daddy are sleeping and that she may come to you when she sees the sun. Role-play how to roll over, stretch, grab lovey and go back to sleep. Then brace yourself for a couple of bad nights, but once she sees how the clock works and that you're not going to give in to her tantrum, my bet is she'll be sleeping better.