All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
The money earned from selling alcohol is forbidden and bad, and thus it should be disposed of by giving it to the poor or using it in the Muslims’ public interests. The money earned from selling alcohol directly helps the person to commit what is forbidden. Regarding this, the Prophet stated that Allah, the Exalted, has prohibited the consumption of the price of alcohol.
If that is the case, your father and brother are obliged to repent to Allah, the Exalted, and give up selling alcohol. In addition, the money earned from selling alcohol is haram and is not permissible to be spent by them for eating or fulfilling their interests or the interests of those under their custody. You are also not allowed to eat from this money unless of an overwhelming necessity, such as when you have no money at all or a job from which you could spend without your father's expenditure.
Regarding that girl’s family’s rejection of your marriage to her due to the bad reputation of your father and brother, her father has the right to decide who could marry his daughter and thus he could accept or reject whomever he wants in light of his daughter’s interest. However, he should not reject whomever he fully knows his religious uprightness and good ethics merely due to the dissoluteness of his father or brother. Allah, the Exalted, says (what means): {… And every soul earns not [blame] except against itself, and no bearer of burdens will bear the burden of another} [Quran 6:164] and in the Hadith narrated by Ahmad, At-Tirmithi, and Ibn Maajah, “No criminal commits a crime but he brings (the punishment for that) upon himself.”
Allah knows best.