The person speaking at the end of the poem, "The Lady of Shalott," is none other than the Lady of Shalottt herself.
'They cross'd themselves, their stars they blest,
Knight, minstrel, abbot, squire, and guest.
There lay a parchment on her breast,
That puzzled more than all the rest,
The wellfed wits at Camelot.
'The web was woven curiously,
The charm is broken utterly,
Draw near and fear not,—this is I,
The Lady of Shalott.'
She addresses herself, as 'I', then repeats her name, 'The Lady of Shalott', revealing that it was her who was last to speak.
I hope this helps you.
