IS What is forgotten is really not forgotten?

Answer 1

Metaphorically? No clue... Technically our subconscious retains all memory no matter what. So even if we can or cannot recall whatever specific memory it is still there, but irretrievable. Though we cannot recall our subconscious memories at will we can be reconnected by feelings or events that let us access our subconscious for a small fragment of that memory which we put back together once we retrieve it.

So technically no, if a memory is had, it is forever. Though not always accessible consciously.