that's how strong my love is

Your words express a beautiful sentiment! If you're looking for a poetic or lyrical way to complete or expand on "that's how strong my love is," here's a gentle suggestion: "That's how strong my love is—
unchanging like the stars above,
steady like the ocean tides,
deep as the roots of ancient trees,
and endless as the sky." Would you like me to help you turn this into a full poem, a song, or something else?