Every Action Has An Equal and Opposite Reaction (Newton's Third Law.)

So if this is the case, would gravity have an equal-opposing force?

From asking around I still haven't got a very clear answer; those who I've talked to seem to believe there isn't one- that gravity is actually a singularity [a one way force] which somehow "just works", others think it differently- believing there is an opposing force of which prevents gravity from compressing masses more than it already does...

So what one is the right answer... (if either!)

-Thanks.