What is the solution to the problem of a Sunni young man marrying an Alawite girl, whose family rejects this marriage due to the difference in madhhab, and what are the implications if one of the parties changes their madhhab?

The Nusayri (Alawi) sect is misguided and deviant, outside the fold of Islam, by the consensus of scholars. It is not permissible to marry their women or consume their slaughtered animals because they are disbelievers who deify Ali, may Allah be pleased with him. Sheikh al-Islam Ibn Taymiyyah mentioned that they are disbelievers by the consensus of Muslims, and it is not permissible to eat their slaughtered animals, marry their women, or accept jizyah from them. Therefore, it is not permissible to marry an Alawi woman until she repents, abandons her false doctrine, and embraces Islam, based on the Almighty's saying: (And do not marry polytheistic women until they believe). And whoever considers converting to Alawism for the sake of marriage has disbelieved and will lose both his worldly life and the Hereafter.