This is a tricky question in which these points are often brought up in debates between theists and atheists. I figure that it has to be one way or the other here though. If ‘good’ really has no objective antithesis then in what other way can we define what we’re supposed to oppose or not be indifferent to?
Without any objective definition of good there appears to be only one other alternative that I can think of, one of which the OP may not like: utilitarianism, meaning actions that produce the greatest amount of ‘good’ outcomes for the largest amount of people. I’m definitely not a diehard utilitarian though, and personally any action that does the greatest amount of good for most others, but comes at the expense of the welfare of other ‘non-bad’ entities needs to be seriously reviewed in my opinion.
Ironically I feel that individual liberty, when this doesn’t hurt the individual liberties of others, ultimately does lead to a positive version of utilitarianism in an inadvertant way. I love these types of questions since they allow me to demonstrate my pseudointellectualism, but I am serious about my post here, and I stand by my last answer. The problem tends to be that individualism, like utilitarianism can go horribly wrong, which is why they probably say the road to hell is paved with good intentions.