What is the ruling of the Shari'ah on dealing with an alcoholic father who does not provide for his family, associates with disreputable women, abuses the religious mother of his children, and is hated by his children?

You must obey your father and treat him kindly, even if he mistreats you, for the father's right to kindness and obedience in what is good does not lapse. What your father has done by violating Allah's rights and committing forbidden acts are great sins from which he must repent. If possible, advise him indirectly or inform someone who can prevent him from committing sins.