everybody's gotta learn sometime

Recently I thought a lot about the movie The Eternal Sunshine of the Spotless Mind. And I've been wondering if it would be helpful to have your painful memories erased? Wouldn't it be easier to cope and to start new without feeling devastated or maybe afraid of new beginnings? Do we really need to constantly be reminded of unhappy times, while being unhappy in the present as well? Wouldn't we be more optimistic? Since we wouldn't know, we wouldn't miss these memories, right? Would every relationship feel like the first one? Every crush or love like the first one? Would we make the same mistakes again and again?