Actually, currently, there is no known way to decrypt Pretty Good Privacy encrypted documents. There are theoretical ways to break old versions, but none that have been used to actually open a message. For example, researchers found that one old version could be cracked, but it would take an estimated 53 million years to break a single message, using the entire computing power of the US government (or something like that).

It is true that there is no such thing as 100% security. The current model for people who are securing systems follows an approach of cost vs benefit - is the cost to an attacker in terms of time, training and resources worth the effort of breaking the system. For your e-mails, PGP would meet that test - it would take much more to decrypt your message than the information in the message would be worth to an attacker.

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