Hello @sonofremi, You do address the prompt and you explore motivation of the character. It is a story heard many times. People 'grow apart'. As a curator I say you did a good job. As a reader and a person I say, you failed to arouse sympathy in me for your character.
I've lived a long time. One of the things I learned in life is that people often try to deflect responsibility for their choices. Marriage is a really hard thing. It is not just a physical union, it is a troth, a promise. It is a test of loyalty like no other.
Mr. Simpson justifies breaking this most solemn oath, this lifetime commitment because his marriage is no longer 'satisfying'. To me, that is a commentary on his character and not on the marriage. I think his lack of moral strength and loyalty will follow him in other commitments he makes for the rest of his life.
I would not say this as a curator, but I can say it as a reader responding to your story. You did a very good job of arousing my interest. A writer can wish for nothing more that.
Good writing.