My personal view is that you should stick to the important point:
You are a citizen of the EU, holding an Italian passport. You were born in Italy, and lived there for the first 25 years of your life. You own property in Italy, and pay the necessary Italian taxes.
Unfortunately, the rules state: you must have been ordinarily resident in the European Economic Area (EEA) and/or Switzerland and/or the overseas territories for the three years before the 'first day of the first academic year of the course'
So, you need to justify your failure to meet this requirement. You might consider something along the lines of:
"Although I have lived and worked in the USA for the last five years in order to improve my English language and to raise money for further study, I have retained very close links with Italy, returning several times, often for a few months, to spend time with my family and maintain my property. Indeed, in the last three years I have spent a total of seven months home in Italy. I now wish to carry out my plan of returning home to the European Union to study.
"In view of these circumstances, I would ask you to re-consider your decision to classify me as an overseas student."