K.D.
Sounds like she is teething. Give her some oragel and a little tyn before bed, see if that gets her through the night better. If she was sleeping and now she's not, something is going on like teething or an ear infection. 8 months is prime teeth pain time. When she is nursing for a short time at night, she is using you as a pacificer. Don't let her. Get her something to chew on if you don't like the pacificer. Lord I couldn't of made it without one. Sucking is natural and doesn't alway mean they are hungry. If the oragel doesn't get her some sleep, get her ears checked out.
By the way, mine are 4 and 2 years old and I still have the monitor on, NO way could I give that up, and you shouldn't either if you don't want to. I feel like my kids are safe when it is on. If you want a good book to read, "Babywise" is the best for figuring out sleep/feeding problems. Both of mine slept 8-10 hours a night using Babywise by 8 weeks old.
But me, I still think it's the teeth.
Hope you BOTH get some sleep, hope it helped, good luck.