sleep training

my daughter is 20 months and still wakes up at least twice at night. I got her used to breastfeeding her to sleep. her naps are usually 1 hour and it's been very hard to have a consistent nap schedule as sometimes she'll nap and sometimes she'll fight naps. even if she's fuzzy and sleepy she has a hard time falling asleep unless I'm breastfeeding and sometimes even if I breastfeed. I'm feeling very exhausted and resentful. I need sleep and consistency. If anyone has some insight or suggestions I'd really appreciate that