Something I was told seemed to answer this for me. I believe this idea, like all great ideas originally came from Bill Cosby
The question isn't half full or half empty, but rather, are you the drinker or the pourer? Its a matter of perspective. If you are the pourer half is more than the drinker deserves. If you are the drinker, you would say half isn't enough. So which one are you in the situation, drinker or pourer?