Q.branches of lime tree break off easy
If the branches to my lime tree break off easy, is it dead? I am in zone 8b. Planted a key lime tree from a pot we bought at Home Depot last spring. Took it home and was planted in the backyard. It was watered everyday. This spring it looks dead. The branches look very dry and break off easy. What can I do to revive it or should I just buy another lime tree?

How do the leaves of the tree look? Are they yellowed/brown? - have they fallen off the tree?
Did you fertilize your lime tree? Did you plant it in a location where it got plenty of sun?
While lime trees should be watered consistently they should not be watered everyday. Too much watering can kill them. I suspect this may be what is happening.
I would like you to perform a scratch test on your lime tree to see if it is truly dead. Instructions on how to do a scratch test can be found here:
http://www.starkbros.com/blog/how-to-do-a-scratch-test/
If the scratch test shows life, you can try to revive it following the course of care outlined in the following article:
https://www.gardeningknowhow.com/edible/fruits/lime/lime-tree-tips-care-of-lime-trees.htm