I like Nick's distinction between relativism and pluralism.
For me the core question here is "Do I have a faith and belief system that I can hold onto?" One of the stages in inter-religious dialog is to become grounded in one's own belief. This is not relativism. It is being a centered individual inter-related with everyone else - in a pluralistic world.
Just because it is not hard and fast does not mean that it is relative.
Haidt, through surveys in many cultures has identified five moral foundations:
Care/Harm,
Fairness/Cheating,
Loyalty/Betrayal,
Authority/Subversion
Sanctity/Degradation
By the way, he says liberals only value 1 & 2 in political conversations. Perhaps that is an issue here, also.
We like to say morals are universal, instinctual, part of the evolution of a pro-social animal. Infants and toddlers recognize help/hindrance, fairness, and believe in retributive justice. The problem is that these moral tendencies are circumscribed by self-centered and tribal-centered perspectives.
I think, then, that the toddler who insists in fair distribution of goods among animate objects can be influenced into perceiving that some group of animate objects don't count any more. This is the true relativity. Only my relations count.
Take Care
Dutch