For behavior that extreme, especially a relatively sudden onset, I'd be looking at illness or pain of some sort. 2-year molars? Ear infection?
For the moment I'd ride it out, give lots of cuddles and then some. Try some pain meds maybe 20 minutes before bed, see if it makes a difference; if it does, you have a clue that something else is amiss that a doctor might be needed for. Can she "nap" in your bed, the two of you take a snooze together? Or read a book together and just cuddle if she's ending her need for a nap? (on of mine was getting there at this age, the other had already given them up at 18 mo
)
Also, is it just you she grabs for?