A related term for an habitual liar is mythomaniac.

One writer on the Internet speculates:

"Kleptomania is taken from the Greek, meaning a mania for stealing - if there were an equivalent word for compulsive lying it would logically be Pseftomania (Psefto=to lie). But this word does not actually seem to exist. It seems the technical term is either compulsive or pathological liar."

The sense I am trying to convey is that of a home where a child grows up being forced to not tell the truth, for any number of reasons — fear of punishment, covering up for a parent, etc. In the pseftogenic home, the pressure to lie is more likely coming from mom, rather than internally or from peers (sorry Zed).

It may not need to be a single word. An approximate antonym, one that I personally like, is truth-seeking. This suggests a phrase something like truth-denying (abusing or shattering?) or maybe just slippery? Undermining is also close.

Richard