I think this song is about blindly following your most basic emotions without giving any thought to it in the moment. You give up all control of your life to your most basic urges like you were aimlessly drifting down a river with the current. Like a gambler who just throws money down and is left to the mercy of randomly dealt cards. It doesn't work out for the narrator, and he is left lonely to reflect on his life choices.
I think this song is about blindly following your most basic emotions without giving any thought to it in the moment. You give up all control of your life to your most basic urges like you were aimlessly drifting down a river with the current. Like a gambler who just throws money down and is left to the mercy of randomly dealt cards. It doesn't work out for the narrator, and he is left lonely to reflect on his life choices.