I totally feel your pain- I too was in tears when I heard the SAD cries of my son at around that same age when we ended his love affair with the pacifier. We did ours a little different -we cut the tip off, unbeknownst to him, so he still kept his "broken pacifier" with him in bed and slept with it in his hand for a few months. Eventually it fell under the bed and he stopped asking for it, so I slipped it away to the memory box. But, I will say, those first two nights were the worst as far as his emotional reaction. After that he asked for it occasionally, but adjusted pretty quickly to not having it. AND we had a younger child who was using pacifiers throughout the day (the exact same ones!) at the time. We encouraged the "big boy" mentality, and reinforced that pacifiers were for babies and he responded well to that and accepted it. Incidentally, we used a similar approach (cold turkey, you're a big boy now...) when potty training and it also worked great, and really fast!
Every once in a while he'll put his younger sister's pacifier in his mouth, but we laugh and he laughs and knows that it's silly.
Good luck - just stick to your guns, stay positive and supportive and you'll get through it soon! I think it's also a good thing to hug and cuddle her when she's sad about it and missing it and tell her you understand that sometimes it's hard to make big changes like this. Growing up is painful at times and this won't be the first time you'll cry together over some growing pain as life changes and babyhood and then childhood slips behind her. :-( Makes me sad just thinking about that...