How does cultural views that exists may affect relationship negatively

Here are two examples:

- In many cases inter-caste marriages fail due to the cultural values set up by the society because certain rules have been set up by the society that particular individual can marry to someone who's belonging to the same caste and not from the different caste

- Religious rituals are also the other reason which creates a difference in relationships as if a girl/boy isn't able to reciprocate to his/her better half's culture then it's creates a burden in their relationship.