I feel your pain. I am getting up once during the night to feed my 3 month old.
With my 2 year old he did that as well. I started him in day care about that time as well. It took him quite a while to adjust back to a new routine with the day care schedule and drastic change in his life. After a time he did start sleeping through the night again.
Somethings you might try is move that last nap early during the day. So she isn't going to bed for the night 1 1/2 hours before bedtime. If she is awake longer she will sleep longer before her internal clock says enough long sleep.
Until that works, I used to place my son in the swing with all of the lights off and let him listen to the swing music while I dozed on the couch until he fell asleep. Then I would move him back to his crib. I would also place the swing in front of the TV with Baby Einstein playing. It has very soothing music and has a repeat cycle so you don't have to push play over and over again. This worked because he usually fell asleep before he was awake long enough to get hungry and I got some sleep in the meantime.
It is also possible that teething is waking her up during the night.
I don't know if any of this will help in your situation or not, but good luck from one tired mom to another.