Just a thought, please correct me where I am wrong so I can learn.
Justifications creating conflict for the Handmaid’s Tale might be:
People should act within the laws that define what makes a family in order to be known as a worthy person. (Objective premise)
UNLESS
People can freely love the one they choose in order to have the family they desire. (Subjective premise)
The author, in my opinion, is tearing down the objective premise: June and Luke have a rewarding and respectable life/family despite June taking Luke away from his lawfully wedded wife (showing the premise is false). Gilead’s laws punish the natural mother for loving her own baby (showing the premise to be harsh and unnatural ). .
The author, in my opinion, is building up the subjective premise: June loves the one she is with and is rewarded - first with married Luke, later with available Nick, even when she is lawfully wedded to Luke. Same sex couples have satisfying family lives because love is there and love is love. And Moira, out of love was able to give up her child so another couple could have the family they desire. Moira was rewarded through this experience by meeting Odette who becomes her true love. Also, the author demonstrates that though Serena is able to receive as her own a baby taken away from its natural mother, Serena does not truly love the child - demonstrated by her choice to keep her instead of letting the baby be free where she can have her best life. So the second premise stands that only where there is love can a family truly be created.
Admittedly I have not seen how the story finally ends to know if this trend continues. But, for a working model of how justifications exist and are played out in a story does this sound like I’m at least hovering in the right neighborhood or does my understanding need a complete overhaul (again 
) .