How is Proctor's characterization of his wife ironic in The Crucible?

Arthur Miller's The Crucible is not a
particularly ironic work; however, there is some irony in how John Proctor characterizes
his wife.  Proctor has committed adultery with Abigail Williams, a serving girl, in his
own house.  Elizabeth suspected the relationship and called her husband on it.  He
confessed to the sin/crime and Abigail was ousted from their home.  In the intervening
months, the Proctors' relationship has been awkward and stilted.  He feels guilty and is
trying to regain his wife's trust; she is trying to trust him again and deal with the
inevitable issues of inadequacy.

When they share a scene at
mealtime, Elizabeth is trying to please John and not totally succeeding (the food isn't
seasoned to his taste and she forgot his beverage) and he is trying to please her
(offering to get a dairy cow) but failing because he did not tell the entire truth
regarding his recent chance encounter with Abigail.  When Elizabeth calls John to do
what's right and tell the court the girls are lying, he
explodes:

You
will not judge me more, Elizabeth.... Let you look to your own improvement before you go
to judge your husband any more....  Learn charity, woman.  I have gone tiptoe in this
house all seven month since she is gone.  I have not moved from here to there without I
think to please you, and still an everlasting funeral marches round your heart....  Let
you look sometimes for the goodness in me, and judge me
not.

Here it's clear that
John sees Elizabeth as his judge, living only to condemn him.  Her reply is quiet and
believable:

I
do not judge you.  The magistrate sits in your heart that judges you.  I never thought
you but a good man, John...only somewhat
bewildered.

Proctor has
characterized his wife as a judgmental and condemning presence; the irony is that
Elizabeth is not the one who's making John feel guilty.  It's his own conscience which
keeps him on edge and guilt-ridden.  We believe Elizabeth when she says she thinks he's
a good man; and she confirms it later when she apologizes for being a cold wife whose
low self-image probably prompted his lechery.  No, it's not Elizabeth who is Proctor's
judge.  It's the guilty conscience of a God-fearing man, not his judgmental wife, which
is making him so miserable.