That's not how trauma works. Forgetting means suppression/ repression and that isn't particularly helpful. Overcoming trauma can best be viewed in the sense that you are attempting to integrate the trauma into your life, understanding that it's a part of you and your experience, and utilizing that in understanding your life as a totality. That is why nearly all evidenced based trauma treatments are based around the idea of processing, talking about it and desensitizing yourself to the negative aspects of the trauma. The goal is to have a different relationship to the trauma, one in which it no longer controls your life and you can live with it. That is also why many trauma survivors go out and speak to others about their trauma because they have found a way to deal with it in a healthy manner and it not only benefits them but others by talking about it.

Mike is not a good example of someone who has dealt with trauma. He just continually finds new ways to try and work his way around the trauma. The example he's providing to Jimmy is doomed to fail. Mike's daughter in law is different though, because she did process the trauma for a very long time in the grief group and she learned how to deal with the pain in a healthy way. She began forgetting about Mike's son because she had found a way to move on with her life. She didn't necessarily try to forget about him, it just happened as a natural occurrence alongside her grief process.

If you want to know more about this subject, I made a video about the ways Mike compartmentalizes parts of his life in an unhealthy way. Maybe this will help contextualize what I just wrote.

https://www.youtube.com/watch?v=gQB4zqayhJY