Saudade

Do you know when you are away from your family, friends or anyone you love. That feeling of emptiness, loneliness... In English is used miss. You say I'm missing you... But I don't know if there is another word to describe the feeling (in English). In Portuguese we have a special word for that feeling it is SAUDADES.
We have songs about it, poetry... People say the Portuguese is the only language that has that. Yes, a word for the feeling. Think about your first best friend. You met him/her in school or in your old neighborhood. You were impossible together and after a few years spend all the time you had with each other now... You don't even know where he/she is... I miss that, I miss my first best friend. This nostalgic feeling is SAUDADES.
Once looking up online I got to whole discussion that you have similars words in English for it, but as always when you translate anything it looses a little bit the meaning behind it.  And the best way I found out to describe it was:
Saudade was once described as "the love that remains" or "the love that stays" after someone is gone.
As song by a brazilian singer says: "To com sintomas de Saudades:"
                                                           I got symptoms of Saudades