I can relate! At least your mom asked if you wanted anything. Most of the time my parents don't even do that. And I agree with oxy, we should all speak up when we wanna come too!
Aww, I'm so sorry. I know exactly what you mean. Whenever my parents go somewhere, they just assume I don't wanna go along and leave me home. Sometimes it hurts because, maybe I do wanna go. But you just have to learn to speak up and say, "Hey, I wanna come too." :]