Ventral tegmental area (VTA) + nucleus accumbens → dopamine surge, reward anticipation.
Caudate nucleus → attachment and motivation to pursue the person.
Prefrontal cortex (PFC) → positive bias, suppresses critical thinking, idealization (“rose-colored glasses”).
Oxytocin-rich hypothalamus pathways → bonding, trust, sexual bonding.
➡️ Brain is wired to seek, trust, attach.

Amygdala → threat detection ramps up (“they hurt me”).
Anterior cingulate cortex (ACC) → conflict monitoring; struggles to reconcile love vs. danger.
Hippocampus → encodes painful memory details, making them hard to forget.
➡️ The brain is in cognitive dissonance mode: part still loves, part now perceives danger.

Anterior insula → primary disgust center. Lights up in both physical (rotten food) and moral (betrayal) disgust.
Basal ganglia → supports the “avoid/repel” motor reaction (pulling away, recoiling).
Medial prefrontal cortex → stops romantic idealization, starts moral judgment (“they’re beneath me”).
Deactivation: reward circuits (VTA, nucleus accumbens) quiet down; oxytocin bonding pathways weaken.
➡️ The brain literally flips the switch: person once coded as “rewarding/safe” is now coded as “contaminant/repulsive.”

Ventromedial PFC → regains control, dampens emotional charge.
Default mode network (DMN) → integrates the memory into your broader life story, reducing intrusive salience.
Amygdala + insula calm down unless triggered by reminders.
➡️ Brain recodes them as irrelevant background data, not central to your emotional world.

🌱 Summary in Plain Words

In love: reward, bonding, and idealization circuits dominate.
After betrayal: threat and conflict centers fight with bonding circuits.
In disgust: the brain shuts off reward/bonding areas and recruits the insula to code them as “toxic.”
In indifference: higher prefrontal regions integrate and file them away, so they stop feeling charged.

✨ This shift is protective. Your brain essentially says:

🧠 Structural Brain Changes: Love → Disgust