Somebody Please Explain Situational Ethics To Me

One of the bogeymen of the right is "situational ethics." I will admit that I haven't a clue what it is they mean. Some mean ethical relativism, and that has its own set of problems, but others clearly intend something else and I'm not sure what it is or why it would be so scary.

It could mean that details of the situation play no role in whether an act is morally good or not, but this is clearly false. If I walk up to a woman and ask her to sleep with me, it matters whether that woman is my wife.

It could mean that we all have the same moral responsibilities. But this is of course false, those who marry, those who have kids, those who have elderly parents in their care clearly have responsibilities that others don't.

It could refer to a meta-ethical decision procedure for determining what is the morally right thing to do in a circumstance. When we decide whether to do X or Y, we may appeal to virtue, duty, utility, care, or rights. It could mean pick one and stick with it come hell or high water. But, of course, actions that, all other things being equal, I would never consider doing would in extreme circumstances become morally necessary. While I do not agree with the arguments for the permissibility of torture or American exceptionalism, both of these are examples of conservative arguments that change moral systems in midstream. Again, while I don't buy the argument in either case, there are what Ross called prima facie duties which you should do, all other things being equal, but in the messy real world, all things are never, in fact, equal.

It could simply mean that one must be morally consistent and hold that you live up to whatever moral bar you hold everyone else up to. But this sort of hypocrisy seems much weaker than the charge they are making.

So what else could it mean? Is it really a claim that there is to be no serious moral deliberation, that there is only a set of absolute Divinely given rules? Is it an attempt to substitute theology for ethics? Please, somebody explain to me what they mean by situational ethics.