Help with the meaning of "flu"

[wildflower 67]

Could someone please help me figure out what "flu" means on this information I found written in an box of old photos. It reads as follows:

Sig. Annunziata Di Domenico
(flu Luigi)
Macchia Valfortore
Compobasso, Italia

Also, I could use help with the second line below. Possible address? And it looks like the U was written over an A in "Salitu".

Singer Salvatore Di Domenico
Salitu St. Michele N. 22
(Compobosso Riccia
Italy

Thanks so much!

[liviomoreno]

I believe it is:

(fu Luigi) = daughter of deceased Luigi

Salita San Michele n. 22

(Next time post the images...)

[wildflower 67]

Thank you! I wondered if it was her father's name or her maiden name. Here is the image..

[liviomoreno]

I still believe my interpretation is correct.
And I also believe it was meant to be "Signor Salvatore Di Domenico"...