Consciousness is often said to disappear in deep, dreamless sleep. We argue that this assumption is oversimplified. Unless dreamless sleep is defined as unconscious from the outset there are good empirical and theoretical reasons for saying that a range of different types of sleep experience, some of which are distinct from dreaming, can occur in all stages of sleep.
if a memory never forms it may as well not have happened
That is an interesting philosophical question.
If suffering is not remembered, was there even suffering? And if there was, does it matter? I can think of a few counterexamples of that, for example: a killer who tortures his victim before killing them.
