A single word for life after having been changed by a cataclysmic event
Solution 1:
In the given example sentence, the word perturbed can replace divergent while implying "deviated from their original course".
Everything that transpired after her brother's suicide, every opportunity taken or ignored, every decision made painstakingly or with ease, were perturbed from the path her life would have taken had her brother decided to change even one of his actions that day.
M-W:
perturb transitive verb
3 : to cause to experience a perturbation
perturbation noun
2 : a disturbance of motion, course, arrangement, or state of equilibrium; especially : a disturbance of the regular and usually elliptical course of motion of a celestial body that is produced by some force additional to that which causes its regular motion
a perturbation in the planet's orbit
Solution 2:
How about conditioned?
OD:
condition: have a significant influence on or determine (the manner or outcome of something)
You example (paraphrased):
My mother's suicide when I was 12 years old conditioned my entire life.
Solution 3:
You might consider
watershed
Defined in Oxford Dictionaries as:
- An event or period marking a turning point in a situation: ‘these works were a watershed in the history of music’