To accomplish anything of real importance, whether it is completing a project or sustaining a committed relationship, requires perseverance.
Perseverance means applying continued effort to achieve something, despite difficulties or delays; it is the expression of determination.
"No one succeeds without effort... Those who succeed owe their success to perseverance." ~ Ramana Maharshi
"It's not that I'm so smart, it's just that I stay with problems longer." ~ Albert Einstein