I am sure everyone has given good advice. I would do one of two things:
1. Take a big step backwards with daycare. Take her there and spend time there with you there for as long as you can (I did half a day) then you both go home again. Do this a few times before you take her there by herself. Allow her to spend one on one time with the carers. Spend a few minutes at a time out of the room and come back in. She has to start making a connection of you coming back.
2. Pull her from childcare and take her to playgroups instead. That way you can show her how to socialise the way you think is appropriate and she doesnt feel that she will leave.

I hope this helps. I personally dont think it is a matter of her just having to get used to it. You can do it slowly if you really believe that she will get a benefit out of being there. I think she can get a benefit out of childcare but she has to first have a really strong relationship with her carer.
Big hugs!