Your problem then is that she doesn't know how to get to sleep without being breastfed. As she is now older, she is less reliant on milk in her diet and may well often not actually want any milk. She might be full, she might just not feel like having milk. But she knows she has to have milk in order to go to sleep.
Her problem at this very moment may well be that she's full (I assume you fed her when she first went to bed) so really doesn't want feeding. But she is so tired and wants to go to sleep. But the little mite can't go to sleep on her own so she is frustrated and crying. She's just so tired.
There is little to resolve this at this very moment - just do what you can to help her sleep.
Longer term you could do with developing ways of teacher her to go to sleep without being fed. For the sake of your own exhaustion, that is probably best done for daytime naps and bedtime first - rather than wake ups.
I's recommend a form of gradual withdrawal. Whereby you stay with her, reassuring, shushing, patting, stroking, tickling, singing, whispering, whatever works. But don't pick her up - try to teach her to settle in the cot, with you (or DH) there with lots of care and nurturing reassurance.
If you search for a thread called 'what worked for us' - the OP gives a great explanation of a form of gradual withdrawal used for an older baby.