The Collaborative International Dictionary of English v.0.48:

Woefulness \Woe"ful*ness\, Wofulness \Wo"ful*ness\, n.
   The quality or state of being woeful; misery; wretchedness.
   [1913 Webster]

WordNet (r) 3.0 (2006):

woefulness
    n 1: intense mournfulness [syn: woe, woefulness]