Messages not responding

Question

My "friend" was being an idiot, as usual, and was sending me hundreds of messages on iMessage really quickly. There was no problem at first, but then I went over to chrome for half a second to look up something, and then when I came back, Messages was completely frozen. I force quit and then tried to reopen it as you usually do when an app ins't responding, but then it wouldn't reopen. It would just sit there and use ~100% of one of my CPUs and just say not responding. I also looked at my phone and iPod who recieved the texts and managed to delete the conversations entirely. I am unable to do anything with the computer version and don't know of any way to fix it. Any suggestions greatly appreciated.

Answer 1

Read this whole message before doing anything.
Back up all data.
Quit Messages if it’s running.
Step 1
Hold down the option key and select
Go ▹ Library
from the Finder menu bar. Move the following items from the Library folder to the Trash (either may not exist):
Caches/com.apple.Messages
Caches/com.apple.imfoundation.IMRemoteURLConnectionAgent
Leave the Library folder open. Log out and log back in. Try Messages again. If it works now, stop here. Close the Library folder.
Step 2
If you still have problems, quit Messages again. Go back to the Finder and move the following item from the open Library folder to the Desktop:
Messages
Note: you are not moving the Messages application. You’re moving a folder named “Messages.”
Test. If Messages now works, delete the Messages folder on the Desktop. Otherwise, quit Messages again. Put back the folder you moved, overwriting the newer one that may have been created in its place, and continue.
Step 3
In the Preferences subfolder, there may be several files having names that begin with any of the following strings:
com.apple.iChat
com.apple.imdsmsrecordstore
com.apple.imessage
com.apple.imservice
Move them all to the Desktop. There may also be a file with the name "com.apple.imagent.plist". Move that to the Trash.
Also in the Preferences folder, there's a subfolder named "ByHost". Open it and do the same thing.
Log out and log back in. Test again. This time Messages should perform normally, but your settings will be lost. You may be able to put back some of the files you moved to the Desktop in this step. Relaunch and test after each one. Eventually you should find one or more that causes Messages to malfunction. Delete those files and recreate whatever settings they contained.
If the issue is still not resolved, quit Messages again and put all the items you moved to the Desktop back where they were. You don’t need to replace the items you moved to the Trash. Stop here and post again.
If you later decide that you don’t like the results of steps 2 and 3, you can undo them completely by quitting Messages and restoring the items you deleted in those steps from your backup.