I had a past. I know that. I remember it. Why would there only be shadows and nothingness where others had people and memories?
sometimes things are better left unseen.
your past is drenched in smoke and flame. perhaps you cannot find your past for the fog of it, your vision limited by the very thing you seek to see. maybe your past is this emptiness you seek to fill.
forcing open a thing that binds itself shut leads only to wounds that gape and weep forever. what can be learned will be taught, eventually - all you need is patience.
in any case, i have it on rather good authority that your companions' memories are no more intact than yours, whether they know it or not, so you're not alone in your blindness. there is much to be learned for all of you.