Here is what I found:
The Symbolic Meaning of the Turtle
Sea turtles are more ancient than any other vertebrate animal: they watched the dinosaurs evolve and even become extinct. They survived the Earth's ages of ice and continue to flourish.
Through the ages and cultures, turtles have many meanings. Some believe the turtle is the symbol of the primal mother and connected to the lunar cycle.
In the Far East it was believed the shell was a symbol of heaven and the square underside was a symbol of earth. The turtle could help you unite heaven and earth within your own life.
Ancient myths describe the world as resting on the turtle's back.
Others believe the turtle is associated with longevity, great age, and wisdom.
The turtle naturally withdraws and goes within when in turmoil. It does not need to learn the importance of this, it naturally knows.
The turtle's whole life is one of steadfastness of effort and patience. Slow and steady: A life of 'non-doing'. There is a saying "home is where the heart is". The turtle is always at home within itself.
May we learn from these ancient creatures.
and...
TURTLE is Symbol of Longevity and Heaven's Blessings. Turtles seem to possess an enviable and god-like resistance to aging and Represents Long Life. The Turtle is a Symbol of Good Fortune and is a positive omen bringing 10,000 years of happiness. The turtle carries the world on its back. This is a symbol of fertility, vitality, and great patience. The Chinese believed these animals foretold future events. The Turtle protects by teaching the family to protect themselves. She brings the blessings of heaven to the home. Turtle symbolizes both the stability of earth energy, and the magical mysteries of heaven. It is a Symbol of Good Luck, LOVE and Health.
http://wiki.answers.com/Q/What_is_the_symbolic_meaning_of_a_turtle
I've never been superstitious or prone to subscribing to ancient beliefs, yet this is one that I think I'll hold onto. I'll take any positive omens, wisdom, or good luck this little turtle wants to send my way! And if nothing else, it'll be a constant reminder of the value of effort and patience. If the turtle can outlast the dinosaur, I can outlast whatever it is that comes my way.
Things happen for a reason. I've always believed this to be true. Clearly it will take time and patience to find the reason behind the rollercoaster ride I've been on. At least I've got my little turtle to carry me through!