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FAQ 12: Why doesn't my baby sleep through the night? Why does my baby wake up often to nurse at night 

Nursing to sleep is a biological norm, Your child is wired to do so. Any time spent at the breast helps build your supply and gives your child immunities through your milk. The breast is your child's safe place where they feel warm and secure. It is normal for a child to fall asleep at the breast. Suckling, the closeness, the warmth, the hormones in milk, are all conducive to falling asleep. It is developmentally appropriate. She will outgrow the need as she grows. Also a child would know that different people who care for them do so differently. When with you, She expects to fall asleep at the breast while when with the dad, she will find an alternative: rocking, cuddling, snuggling, singing, carrying etc. Trust your child and your husband/family/caretakers to find what works for them.

Kids start sleeping longer when they are developmentally ready for it.

Try to rest/ sleep with the child when possible. Get some additional help with your chores/ delegate them to family members/ do them once your partner is at home so that you're not burdened.

Breastfed children nurse through the night and for a good reason. These links should be useful: