IMO, the first is worse. It doesn't seem that memories of pain will actually hurt you, unless they come with effects other than just memory, like, for example, PTSD. And the pain may have been in the past, but just because you don't remember it doesn't mean it's the same as never having happened. The suffering is still important. Just like you'd actively avoid suffering in the future even though it hasn't happened yet, pain in the past is equally real and undesired.