Do couples need the same moral alignment?

Not identical, but compatible. Couples with aligned good-evil values (both Good or both Evil) tend toward stability. Chaotic-Lawful differences can work with flexibility.

Can a Good person have a healthy relationship with an Evil person?

Very difficult. Evil characters may manipulate or exploit Good partners. Power imbalances and conflicting values create dysfunction and emotional harm.

How do moral alignment differences cause conflict?

Disagreements on fairness (Lawful vs. Chaotic), sacrifice (Good vs. Evil), or trust fundamentally clash. Values conflict becomes personal and unresolvable.

Can alignment change bring couples together?

Possibly. If one partner grows toward alignment with the other through reflection and commitment, it can strengthen relationships. Growth requires genuine change.