I feel your pain! I'll just tell you of my experience and hope that you can get something out of it. When ds was around that age, I stopped nursing him to sleep because he would simply not go to sleep from just that. He would get his fill, then roll around, and play and it would end up being a 1-2hr. battle. So, instead of nursing him to sleep, I started bouncing him on the edge of the bed (with sound machine on "rain"). Some nights it would take like 30 min. or more, but I also realized I had to wait till he was in a deep sleep (limp limbs, no facial expressions) before I tried to lay him down or else he would start rooting around to nurse, and I'd end up laying there for another hr. or so. So, I just learned that it was easier for me to get him to sleep without the boob, and just go back to nurse when he woke which was at first about 1-2hr. after he went to bed.
Now my son is 18mo. and dh has taken over nighttime (started when ds was around 12 mo.), because it is much quicker for him to get him to sleep. Dh just lays ds on a pillow (vertical) on the bed, lays beside him, and gently bounces him till he goes to sleep while saying "shhh" and "go night-night" in a low voice, and we still use the sound machine. He's out every night in 10min. or less. I think a consistent sleep schedule is extremely important though. Ds goes to bed every night at 9pm, is up by 8:30am, and nap is 1pm-3pm.
I'll also tell you though that when ds was younger, he would use me as a paci throughout the night alot. I would wake up some mornings and my nipple would be so sore. I'd have to wait till he was really in a deep sleep before I detached. Like, the sucking was dwindling, and then I would detach and hold my boob to where i wasn't touching him at all, cuz if there was any skin contact he would root till he got my nipple again. So I pulled my self off completely, then layed there for a min. till I could sneak away. I think it's just something they do less and less as they get older. He does still do it sometimes but only when he is sick or doesn't feel good. Other than that, he goes 2-4hr. stretches before i need to come back in to nurse, and once I'm in the bed with him he just nurses till he's full, then rolls over. I use to think I would never get to that point, but like I said I think once they get older they don't need it for comfort as much.
Sorry if I'm rambling or it sounds confusing, but I hope I've helped even if it's just to let you know that you're not alone, and it will pass. She's not going to be nursing all night at your breast forever.