going with the flow

deadpan dispassionate emotionless impassive laid-back reticent

along for the ride apathetic blah callous chill cold coldhearted cool flat frigid glacial hard-boiled hard-hearted heartless indifferent insensitive listless marble obdurate passionless phlegmatic quiet reserved rolling with the punches thick-skinned uncompassionate undemonstrative unexcitable unfeeling unimpressionable unresponsive unsympathetic

emotional feeling passionate

caring excitable responsive