I'm a first-generation Quebecois in America (ugh!) and my French = NULL. I studied it some on my own as a kid and took it for 5 years in school. I also studied Latin for 2 years, and German and Chinese for 1. I tried, I really did.
I can't speak a single damn one of them and can barely read a tourist map.
I studied linguistics for 2 years and was very good at it, but it simply feels impossible to learn another language. The amount of rote memorization, unusual grammar, and idioms makes the task seem insurmountable; I'm done trying. I guess I'm just lazy.
A joke they told in my language classes was that a person who spoke three languages was trilingual, a person who spoke two was bilingual, and a person who spoke one was an American. Without having exposure to many different languages at an early age - not just exposure but living amongst them - Americans are pretty much doomed when it comes to learning a second language. Before the age of 4 children can acquire just about any language with ease, and this decreases until the age of 11 or 12 or so - after that, its really really hard to learn another.
It sucks living in New York City and feeling like I'm the only person who doesn't speak another language, but that's just life. At least I speak only English and not only French.