I talk but have no mouth, I listen but have no ears. You speak first, I speak second. What am I?

I shimmer, I stutter, I struggle to stay, I brighten the dark, then fade away.

Kings and queens won't let it fall, But a jack hit his and lost it all, It used to name a minted wealth, But now is meant for oral health.

I get blamed for bad lighting, bad hair, and occasionally bad decisions.

I connect what stands apart, Yet I have no hands or heart. I carry messages near and far, Linking people, places, every star. With many paths, I do my work, What am I, where connections lurk?