As a Shaman I learned to never dwell into the past. The past is dangerous territory unless you know how to navigate it. If you bring those emotions back from your past. These emotions will effect the here and now, potentially future events too. I am still learning this lesson that way I can grow from it, and not look back so much on then to focus on now. Our past has these scars it creates. Scars that we do not need opened. Unless we are strong enough to overcome the pain from those events. Obtain the energy we need to make that energy part of us.
For those who are not Shamans and simply practice magick as a Pagan or Wiccan. Simply let go of the past, and never speak of it. Unless it is happy moments that bring positive energy. Other than this be wise to not dwell on what will never matter now. Merely focus on the now and everything now has to offer you and those you love very much.
This is a simple lesson anyone can follow.