Immediate solution to try: Use a mail client to access your mailbox with IMAP or POP3; GMail may be more tolerant that way. Long-term solution: Stop using Google. Why? Not just because of this type of shenanigans, but because Google spies on you: * It keeps a copy of all of your correspondence, even if you delete it. * (Rephrased) The US National Security Agency (NSA) has gotten access to much of your correspondence,…
Google did no such thing. What Snowden revealed was that the NSA knew at that time the SSL connections from a user to Google were terminated at the GFE, and all the traffic between Google data centers were in cleartext. That includes, for example, a request from an application to store some user data in a database or storage system, or the replication between data centers of user data for redundancy purposes. NSA then wiretapped these communication links.
See this leaked NSA slide: https://commons.wikimedia.org/wiki/File:NSA_Muscular_Google_...