LOL!!
I know how you feel. My in-laws are Greek and all that I know how to say after 20 years is "tikanis, cala, and opa"-- oh, and "scata" or something like that.
Time to break out my Zorba the Greek video again!
I only lived in spanish-speaking countries for the first 4- 5 years of my life. However, my folks demanded that I speak the "mother tongue" around the house. I hated it as a child, but later in life was very thankful that my parents insisted on it.
It's allowed me to understand Latin, and the root words for Romance languages.
And, it also comes in handy, when I want to goof on people.
(sorry for the continuous threadjack, hog)