You´re question confused me, because everytime I wanted to give you an example, I didn´t know, which one I should take. Then I googled it and found out that: "allein" is the correct written form and "alleine" is used when people speak. It´s more informal. Hope that helped. :)

Hello, "Alleine" is the colloquial form of "allein" Ich bin allein. Das Kind kann schon allein laufen. Herr Müller ist allein erziehend See: http://www.duden.de/rechtschreibung/allein_Adjektiv