I'm sorry to hear about the difficult situation you experienced. While I cannot know the specific details of your affair partner's behavior, I can offer some general insights into why such changes might occur:
Guilt and Shame: After the divorce is finalized, your affair partner may start feeling guilty about the affair. The reality of the divorce being official can trigger feelings of shame and remorse, leading them to distance themselves from the affair to cope with their emotions.
Fear of Commitment: Your affair partner might have been comfortable in the affair when there was no real commitment or pressure. However, as the possibility of a serious relationship loomed closer, they might have become fearful of commitment and the responsibilities that come with it.
Fear of Social Stigma: Now that the divorce is finalized, your affair partner might fear the social stigma associated with starting a new relationship immediately after ending a marriage. They may want to avoid judgment from friends, family, or colleagues.
Need for Emotional Space: Divorces are emotionally draining processes. Once the divorce is over, your affair partner might feel the need for emotional space and time to heal from the divorce before considering a new relationship.
Personal Growth and Change: Going through a divorce can be a transformative experience. Your affair partner might have undergone personal growth and realized that the dynamics of your relationship were not as healthy as they initially thought.
Reassessment of Priorities: With the divorce finalized, your affair partner may have reevaluated their life priorities, goals, and values. This reassessment could have led them to believe that starting a new life with you was not in line with their current priorities.
Fear of Rebound Relationship: Your affair partner might have become wary of jumping into a new relationship right after a divorce, fearing it could be a rebound and not based on genuine emotions.
Red Flags and Toxicity: If your affair partner raised concerns about red flags and toxicity, it's essential to reflect on your behavior and actions in the relationship. Sometimes, people may tolerate certain behaviors during an affair, but once the stakes are higher in a serious relationship, they may reconsider the impact of those actions.
In any case, it's important to recognize that relationships built on affairs can be complicated and emotionally charged. If the relationship is not working out, it might be best to focus on personal growth and healing before pursuing new romantic connections. Remember to take care of yourself during this challenging time and seek support from friends, family, or a therapist if needed.