Nermin comes from Turkish and from the websites I listed below, it means "soft." The spellings Nermeen and Nermine also exist because the Turkish name gets borrowed and transcripted into Arabic, then back again to fit the Latin alphabet. Names transcripted from Arabic can result in lots of different (but legitimate) spellings. This is why you see so many different spellings of Muhammad.
http://turkishculture.org/pages.php?ChildID=209&ParentID=12&ID=56&ChildID1=321&miMore=1
http://forum.kusadasi.biz/thread1961-2.html
~~~~~~~~~~~Amanda~~~~~~~~~~~