It certainly is satisfying to hear Carmela's aria develop length and nuance. Her star-crossed love and passion warrant as much cinematic attention as Tony's conflicts and psychopathy, which we've already had hefty doses of. But to me Carmela's attachment to Furio seems notably lackingin self-awareness or psychic growth. Except for the fact that she withstands the urge to consummate her desire, her longing for Furio seems fairly infantile, blind, and persistently adolescent in character. She ignores the obvious fact that her beloved is seriously endangered by her yearnings for him; and rather than recognizing that his flight is an outgrowth of his reciprocation of her feelings, she worries that perhaps he never did love her. The level at which she struggles with her feelings is very basic—"I want him; I can't have him; what anguish!"—rather than her grappling with the implications of falling in love with one of her husband's henchmen. (Isn't Furio yet another ruthless killer, and doesn't she know this? And, isn't she trying to turn the tables on Tony in spades by cuckolding him with his underling?) Granted, love of this kind is blind, at least temporarily, but many people even in the throes of such longing will try to make sense of the emotional bind they're in. At the very least, we would hope that the suffering woman would recognize that she was taking out her rage (at being deprived of the lover) on her daughter and would stick around to make amends, rather than avoiding a mother/daughter confrontation.
Do I blame Carmela? Nope, the writers have clearly given up on granting any of these characters much psychological development, except on a very "lightweight" basis (as when Tony says that some of Carmela's sense of unfulfillment might have a little something to do with him). And after giving their characters the chance to grow emotionally for a full 11 episodes before (and several seasons before that), who can blame the writers for giving up?
As far as Paulie goes, there's a case to be made that, in true Oedipal fashion, this is a guy stuck on his mother. As a result, any indignity (or murder) he perpetrates seems to him like an appropriate response if it defends or avenges a slight against Mom. Whether this extreme devotion is a "reaction formation" (a semblance of love replacing its opposite) masking an actual underlying hatred of his mother—this would be the next analytic question. But my hunch is that Judith is probably right—this character is fundamentally more homage than anything else.