I had the great luck to be raised by natural alpha father. He was the master and commander of his family and was married to a dutiful wife. They had their issues, sure, but they set a great example for me. But in this modern age, such a well-defined man/woman role dichotomy is truly rare.
That said, my father often repeated to me this:
When a couple is married (or in an LTR), they have 3 specific roles:
Husband/Wife, Father/Mother and Boyfriend/Girlfriend
He told me it was the Boyfriend/Girlfriend role where many people eventually fail and thus their relationship is doomed. My father, even now in his 70s, will slap my mom's ass, flirt with her, grab her and kiss her, etc. And I can see my mom relishes it.
So about the roles (using my dad's terminology):
Husband: Master and commander of his ship. Leader. Provider. Decision maker. Warrior. Hunter.
Wife: 1st Mate, keeps the castle clean and and the walls strong, shines the armor, sharpens the swords, cooks the hunt and dresses wounds.
Father: Nature. A guide and a mentor. A solid rock. Teaches strength, survival, defense, offense, respect, gratitude, and honor.
Mother: Nuture. Warm and loving. But enforcer of the castle rules. Teaches reading, writing and arithmetic. Teaches hygiene, manners, and health.
Boyfriend: Fucks and flirts. Flatters her. Keeps himself fit and attractive. Sometimes edgy and unpredictable. Other women want him.
Girlfriend: Spreads her legs for him and sucks his cock. Feeds his ego and makes him feel powerful. Keeps herself fit and attractive. Submissive and charming.
As I've developed into a man, gotten in an LTR, and had a child, I often go back to this list and see how I'm doing. I have failed sometimes. Sometimes life gets the better of me and I forget to be a boyfriend. But the closer I am to fulfilling my roles, the smoother my relationship is. All of it. The bills get paid and my cock gets sucked and the castle walls remain strong.