I have been using Pidgin for about a month with no issues. Then all of a sudden It will not connect to my google talk account.

I found this link that tells you have to set the advanced tab, and that fixed everything for me.

Go to Accounts, choose Edit you Google talk account,
> Click on the advanced tab
> Enter in the following:
Check Force old (port 5223) SSL
Un-Checked: Allow plaintext auth over unencrypted streams
Enter: Connect Port: 443
Enter: Connect Server: talk.google.com
> click on Proxy tab
Proxy type: Use Global Proxy Settings