Yeah, I know I do. Alright, I'm kidding. But there is something to that, and it really is right along the lines that Cindy describes in her Bilingual Families Pages. (I took the headline from the "Myths" page, where she says:)
"Some bilinguals do report feeling that they have a different "personality" for each language. However, this may be because they are acting according to different cultural norms when speaking each of their languages. When speaking English, they assume the cultural role expected of them in English-speaking society. This is different than the cultural role expected of them in German-speaking society, which they assume when speaking German. The change in language cues a change in cultural expectations."
That's certainly true for me, oscillating between my American and my German self.
Cindy's pages are geared towards families, specifically raising children with two languages, but I still found more than enough food for thought for myself. No, I wasn't raised bilingual. I grew up in a German, German-speaking family, learned English and French in school like most German kids, and moved to the United States when I was 29. That's when I became truly bilingual, in my own understanding, and I can tell you exactly when it happened: the morning I realized I had dreamt in English. Even though the dream had been about my German hometown, and German acquaintances. But I disctinctly remember the conversation having been in English.
Funny, innit?