Eh, from a practical standpoint, it does make sense to "assimilate". My wife is Chinese and immigrated here at age 28...she worked her ass off to learn English and while she still struggles (and always will) with more advanced English and with accents, she has built several successful businesses here. She has friends that have lived here for 20-30 years that have never learned it. They watch Chinese tv, only have Chinese friends. My wife has helped them talk to car dealerships, with school officials when one kid was getting beat up and bullied, and many other times. Her sister has been here 10 years and can't do the simplest thing at the DMV or a store that isn't Chinese. Why would you want to be so helpless when it comes to dealing with anything "official"?
If I ever moved somewhere non-English-speaking, job 1 would be learning the language. Hey, if you don't want to, fine, but I would not want to be so dependent on others, and I feel it's pretty arrogant for me to bust over there and demand people change the established means of communication just to save me from making the effort.
None of this means you surrender your culture. And it wouldn't hurt English speakers to learn some other languages either, it's good for you!