What happens after the honeymoon phase

Idk how to put this across in a better way. But I'll try.

I (f) am getting married soon. We met through an arranged set up and really like each other(Alhamdulillah).

The initial phase of the marriage is going to be about getting to know each other better.

I'm wondering what happens after we get into a routine and the honeymoon phase is over. Maybe a year later.. Or even like 4/5 years later...

Do things get monotonous? What are conversation topics like ?

I've been thinking about how the relation of the husband and wife evolves with time. (Not including children, but just the relation between the spouses)

Maybe children and other factors define how the relation evolves. Also, every marriage is different and evolves in a different way. Just attempting to understand it from a general perspective.