Hello Franciso and others,
Because of life's other commitments, I haven't done much re geneaology for a while but hope to make some renewed progress.
My grandmother was a SUSHMEL, and she lived in Trieste. It is interesting to read these comments about the surname originating in Gorizia; in fact I met an elderly relative last year (in Trieste) who told me my grandparents were know as 'i goriziani' (the Gorizians). It seems to fit, cool.
Family lore is that it was German / Bavarian before the Gorizia period. If I learn any more, I will make a new post.
Ciao,
Julian.