How does browning shows that the speaker in the laboratory in disturbed?

In Robert Browning's poem "My Last Duchess," the speaker's disturbed nature is revealed through his obsessive control over the portrait of his deceased wife and his unsettling calmness while recounting her fate. His casual mention of having her "stopped" suggests a chilling detachment from the emotional weight of his actions. Additionally, his possessive attitude and the way he discusses her perceived flaws indicate deep-seated insecurities and a violent temperament, highlighting his disturbed psyche. Overall, the speaker's demeanor and Words create a stark contrast between his refined exterior and his inner turmoil.