I DID nurse my son to sleep, but honestly, I'm not sure if I'd do so again. I didn't mind him taking longer (compared to other babies) to sleep through the night, and I didn't mind that he took his sweet time about self-weaning. What DID trouble me was that my boob became his one and only source of comfort, and I was afraid he'd carry that over to food in general (though that never wound up happening). However, he did seem to carry the idea that falling asleep was challenge -- one that required parental intervention -- well into toddlerhood.
What I honestly do recommend is trying to get her to sleep with as little intervention as possible. Just rock/cradle her, without a whole lot of movement, maybe with a little lullaby. You can do this in a very gentle, nurturing, attachment-parenting way -- but I do recommend making sleep as simple as she'll allow.