One is the lonliest number

With so many people in the world, how is it one can find themself feeling so lonely?

We're a planet comprised of 7 billion people. How is it then that I sometimes feel so alone? And if feeling lonely was't bad enough, throw into that mix the fact that i feel like a foreigner in my own land.  Have you ever had one of those days  where you feel like you are speaking a language so alien that even men from Mars and Women from Venus can't understand you? I have recently read that that whole Mars/Venus thing has been scientifically proven as boloney...we're just different. Well duh!  Do you ever have one of those moments the minute you open your mouth, you feel people are instantly tuning out and hearing only "blah, blah, blah" instead?