While this is pretty bad, the starting scenario is questionable. Let me put this in perspective. Your partner is now successful and given a lot of responsibility. Due to the accumulate pressure, they became short tempered and prone to outburst. As their partner, are you going to abandon them now? Abandon them to pressure and stress? This is basically how midlife crisis men reacts to their wife changing under pressure of childbirth and child rearing, getting new hobbies and seeking adventures and affairs. If the relationship is physically abusive, then something needs to be done. However, in this case, the main character just has ego hurts and decided to rebel, not considering their partner trial and tribulation. It’s pretty sad when we let ego takes over in old age, forgetting the bond and seeking thrills over long term relationship.