The Collaborative International Dictionary of English v.0.48:

Confiding \Con*fid"ing\, a.
   That confides; trustful; unsuspicious. -- Con*fid"ing*ly,
   adv. -- Con*fid"ing*ness, n.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Confide \Con*fide"\, v. i. [imp. & p. p. Confided; p. pr. &
   vb. n. Confiding.] [L. confidere; con- + fidere to trust.
   See Faith, and cf. Affiance.]
   To put faith (in); to repose confidence; to trust; -- usually
   followed by in; as, the prince confides in his ministers.
   [1913 Webster]

         By thy command I rise or fall,
         In thy protection I confide.             --Byron.
   [1913 Webster]

         Judge before friendships, then confide till death.
                                                  --Young.
   [1913 Webster]

WordNet (r) 3.0 (2006):

confiding
    adj 1: willing to entrust personal matters; "first she was
           suspicious, then she became confiding"

Moby Thesaurus II by Grady Ward, 1.0:

38 Moby Thesaurus words for "confiding":
   artless, bluff, blunt, born yesterday, candid, childlike,
   credulous, dependent, depending, direct, frank, guileless, ingenu,
   ingenuous, innocent, naive, open, openhearted, outspoken, plain,
   reliant, relying, simple, simplehearted, simpleminded, sincere,
   single-hearted, single-minded, trustful, trusting, trusty,
   unguarded, unreserved, unsophisticated, unsuspecting, unsuspicious,
   unwary, without suspicion