I had the same issue as yourself not that long ago. You haven't mentioned whether there have been other changes that could account for your daughter's wakings i.e. new room, new sibling. Has this been going on for long ? Could she be teething. With my son it turned out that from being happy to sleep all night in a dark room with the door shut he would settle if I left his door open and landing light on. This took me a few nights to suss out as he couldn't tell me what the matter was!
Somehow I think you need to replace yourself with something else that will comfort your daughter. Next time she awakes I would give her a teddy to hug and tell her that teddy will look after her -sounds a bit stupid but it worked for my son. Have no idea why our little ones after being good sleepers do this. My son's fear of the dark has reduced somewhat and now he doesn't bother with his nightlight anymore. Let us know how you get on. Best of Luck.

Amanda, thanks ever so mush for the advice. I'll start tonight! Fingers crossed and I'll let you know how I get on.
Helen