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 not permissible for the Muslim to stay in a place while witnessing an evil except for a valid reason, such as condemning its doer. Allaah The Almighty Says (what means): {And when you see those who engage in [offensive] discourse concerning Our verses, then turn away from them until they enter into another conversation.}[Quran 6:68] It was narrated on the authority of Jaabir ibn ‘Abdullaah that the Prophet, sallallaahu ‘alayhi wa sallam, said: "Whoever believes in Allaah and in the Last Day should not sit at a table at which wine is served." [At-Tirmithi]
So, you have to forbid this evil in a kind way, and the fact that your father is the doer of the evil is not a Sharee‘ah reason for not forbidding it. If you forbade the evil and it was removed, you would be allowed to stay at the table. But if he persisted and you could not forbid the evil by the tongue, you have to hate this evil by the heart and leave the place. Indeed, forbidding evil by the heart is the weakest level of faith.
However, when you leave this place, leave it gently so that you do not provoke your father. In this case, you are right to leave and you will be rewarded for that – Allaah Willing. For further information, see Fatwa 84348.
Allaah Knows best.