Wow lots of different suggestions going on here. Obviously you don't want her to sleep with you. For some reason she liked it alot and wants to continue.
Kids are so funny sometimes, they all go through stages of insecurity. You need to figure out if she is doing this to be defiant or if she, as some others have suggested, wants more "special" time with you.
If she is just being difficult, try the Nanny show suggestion. Defiance and manipulation are BAD things to let your kids get away with.
If on the other hand she seems clingy and generally otherwise more "dependant" try to work on that. Discuss why she doesn't want to go to bed.. this may take prompting. Maybe she had bad dreams? Maybe she doesn't have enough blankets and is cold? Maybe she has become afraid of the dark? Establish that this is her own special room just like yours is special for you. Sleeping with others can be disturbing (wakes you up) and explain that you don't rest well when she is there and this is not good for you or her. If she is after some snuggle time, sit on the couch under a blanket with her snuggling just before bed reading books or something.
I made the biggest mistake with my second child. My first slept in his own crib and bed from day one home from the hospital. My ex-husband (different dad) though insisted that the second baby be in our room in a bassinet placed right up against our bed. Well the baby never staid in the bassinet and he slept with us until almost two. By then he was literally pushing us off the bed sleeping longways across the width of the bed and kicking us in the back in his sleep.
After being pushed off the bed one night (while dreaming I fell off a cliff) I had enough. I asked my doctor about it and he said just put him in the crib and let him cry himself to sleep it might take a while... For 3 weeks every night I went to sleep hearing him sobbing and he was still crying when I would wake up.
I couldn't take it anymore and I figured out he would be happy sleeping with his brother. They slept together in the same bed until he was 5 then we managed to put them in bunk beds. It took 9 years for him to finally agree to his own room, and even now he sometimes still gets his brother to come sleep with him. He is still 9... I will let you know later if it stops.
Anyway point is continuing letting her sleep with you could cause BIG issues. Nip it in the bud now. Just let her know its not because you don't love her and its just something everyone has to do.