Married to the Male Lead’s Brother

Ning Zhi transmigrated into a female supporting character who ran away from her wedding.
The original novel was a fluffy book on the love between the male and female leads.
The cannon fodder female supporting character, who had also married into a prestigious family, was caught while trying to escape her marriage which had led to her difficult days in the prestigious family.
In addition, her husband was autistic and, for the sake of pursing true love, she made a tragedy out of her own life.
Recalling the awful ending of the female supporting character in the novel, Ning Zhi expressed that she would never try to run away from her marriage. What was wrong with having globs of money? Or was her husband not cute enough?