Who said "Relationships require as much strength as combat."?

This quote is attributed to Sif.

Relationships require as much strength as combat. - Sif

"Relationships require as much strength as combat."

Sif Relationships

"I have waited lifetimes for this moment."

"A warrior's heart beats strongest in battle."

"We are bound by more than just duty."

"The past shapes who we become."

"The key to a happy marriage is communication."

"Marriage is about compromise and understanding."

"Life's greatest treasures are relationships."

"Trust is a luxury I can't afford."