All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
It is impermissible for a girl’s guardian to marry her off to an alcoholic and she should not accept such a marriage. If the father insists on that, she can take the case to the court so as to prevent her father from marrying her off to such a man.
Furthermore, what the father said to his daughter that she can reform her husband after marriage are the words of someone who is quite ignorant of the true state of a drunkard. Her father is throwing her into the fire expecting her to survive. If the case was reversed, it would be more reasonable and acceptable; for men often possess more powerful and influential personalities than women. So, if your friend married that man, he might drag her into the abyss of committing evil and sins incurring perilous repercussions. Hence, this father should fear Allaah The Exalted and shoulder his due and heavy responsibility towards his daughter about which he would be held accountable before Allaah The Almighty. He should prepare himself for such a serious situation. Moreover, the girl should try to find someone who can mediate between her and her father so as to convince him of her stance underlining the gravity and significance of this step.
Allaah Knows best.