Fair enough - it wouldn't be fair to the other kids that prefer to have their parent there I guess.
It is odd how parents can't stay!

Do you go to a Playgroup at all?
Playgroup would be a great chance for her to get used to be around other kids and strange adults, she would have loads of fun, and while she is playing you might get a few minutes to have a cuppa and a chat to some of the other mums?