Seeking nursing advice

I am still nursing my 15 month old twins. I am happy to still be doing that and have no huge desire to start the weaning process. EXCEPT

In the last few weeks Juliette has learned to ask. The first time she did it I was tickled - it was so cute. I always use a pillow when I nurse so she would find a pillow and drag it over to me. Tiny girl dragging big pillow. CUTE

But now, she does it like 5 million times a day. And when I say no she stomps her feet, throws herself to the floor and has a full on temper tantrum. SO frustrating! She also freaks out if I don't nurse her as soon as she wakes up in the morning (which is fine with me) and as soon as she wakes up from her nap (which I'm not keen on).

Kiernan weaned himself at 11 months after we worked on bottle feeding for me to go back to work. I never anticipated the demands to suddenly get higher. And she doesn't want to stop nursing either - she wants to hang on for eons. She's not a newborn - I'm not down with the marathon nursing anymore.

SO. Do I expect she'll start giving up as I continue saying no? Is this common for some children who nurse longer? Does anyone have any advice on how to deal with this?

I obviously know it's not the same for all children - Quinn never asks and the only time he freaks out is if Eric goes to him and not me in the middle of the night.

When she acts this way repeatedly it makes me think I'm going to need to cut her off, and that makes me sad. I don't think I'm ready to be done nursing forever yet.