Memories are sweet, cherish it.

Memories can't be stolen or taken away from us. Memories can be replayed, relieved and rejoiced at any time and in any selected form. Let us hold on to our memories, both sad and happy. Cherish them as one of our greatest assets of life. Don't judge them or think of what "should have been", clean them like we clean the glass of an old photograph, polish them till they shine and make them bright and clear so that we can close our eyes and walk into them, away from the mundane life of today.
Unpleasant memories, don't try to suppress them and don't deny them. Instead of trying to forget bad memories, make friends with them. If we remember them and use it to improve our lives, as the proverb says "failure is stepping stone to success". The incidents may have been very unpleasant, but the memory can be very useful to us to have a better life. 
Of course, the happy memories. They tide us over the stormy and gloomy days if we're willing to keep them alive. They give us warmth on the most chilly and lonely nights. Nurture them and keep them safe. 
We waste so much energy in trying to suppress sad memories. If we could just accept that it did happen to us but it is over now; we would be more free to accept what comes in our present. Memories are sweet, cherish it :)