indifferent, spiritless, uninterested, unresponsive, insensible, apathistical, temperless, unemotioned, disimpassioned, impassible, more...

passionate, enthusiastic, zealous

disinterested, indifferent, uninterested, unconcerned, unimpressed, unmoved, unaffected, uninspired, more...

not caring,   don't care,   not interested,   doesn't care,   no emotion,   not bothered,   not eager,   do not care,   not excited,   lacking emotion