If you have an opportunity and desire, you can ask happily married couples how to live in peace and love for so long.
These wise and experienced people will cheerfully share their ideas and give you a piece of advice. Every couple has a key secret of their own happiness.
For example, ask your grandparents to share their own secret of a long-lasting marriage then you may understand that trust, blind eye and a sense of humor were the main elements of their secret.
Try that and it will be a big honor for me to receive an advice from such wise, smart and reserved people.