Priorities changed, yes it will be like that no "it will be" not "it should be" like that.

Once my friend said your priorities changed after marriage, it's correct and I know for everyone it will change after their marriage, if it's not changed then the cycle will not continue. Our parents priorities also get changed that's why they created a new family/heaven.

If they both continued under their own  parents this new family will not get created, if anyone of them refused to create the new one and wanted to follow their own then the other one wants to compromise. And it is tough for the major things to get compromised like that. That's why God said Mathew 19: 4-6 -

He answered, “Have you not read that he who created them from the beginning made them male and female, and said, ‘Therefore a man shall leave his father and his mother and hold fast to his wife, and the two shall become one flesh’? So they are no longer two but one flesh. What therefore God has joined together, let not man separate.”

It's just all about that priorities changed, it's not like hiding marriage life from parents or friends. Valuing relationship means each may be needed to hide the personal negative matters about the partner just to keep them good and safe.

But all these will be there only when Understanding is there. And understanding each is the toughest task in arranged marriage I felt. And it is too paining to realise if one among them changed and the other not.