Relations in human life are very important. Right from the childhood, the relations of mother, sister, father, brother, grandparents, cousins etc start impacting our life. As we grow, we find ourselves surrounded with extended relations coming from the society and through our social circles. Some of these relations are with us from our birth and go through our life and others are chosen by us. Some are imposed on us and others are by only and only our choice. However, none of the Chosen relations are the ones that impact us through our life except for our better half (husband and wife).
The reason the relation between a husband and wife is the most important from the chosen set of relations, because they have to live their life together and also ensure that the good camaraderie that they carry helps nourish their kids with the values and culture and the societal norms.
When a girl accepts a guy as her husband, she actually is ready to trade her future for her past. She leaves her comfort zone, her parental home to be accepted in her new home. It is like venturing in an unknown territory and setting up a new house from scratch. She leaves behind all her comfort at her parent's home and moves to her Husband's home to make it her new abode with her new family and another set of parents.
(The reason I chose not to write in-laws is I hate the concept and I believe that Parents need to be referred as Parents only irrespective of whether they are girl's own or her husband's.)
The girl when moving from her Parents place where she was always treated like a Princess, certainly would start her journey of wedded life with apprehensions. Her husband has to ensure that she gets the same level of treatment as she was getting at her Parent's place. Her husband's Parents need to treat the new member in their house as their own daughter. The girl also needs to accept her new abode as her house for the rest of the life and should work towards adopting the values and culture of the new family she has joined. Certainly this does not mean that She forgets the values and culture that she was taught by her Parents.
On the other hand, the guy has to be also treated like a Prince Charming by the girl, irrespective of his Pro's and Con's. She might have been waiting for the Knight in Shining Armor, but she needs to now ensure that she treats her husband as one. If her husband is treating her like a Princess, he also deserves to be treated like a Prince. The girl should also treat her husband's Parents as she treated her own Parents. And if she treats them with a little extra respect, the world would be hers.