Be indecisive, beginning to discuss the matter with her (6)
I believe the answer is:
dither
'be indecisive' is the definition.
(I've seen this before)
'beginning to discuss the matter with her' is the wordplay.
'beginning to' says to take the initial letters.
'the matter' becomes 'it' ('it' means a thing or matter).
'with' is a charade indicator (letters next to each other).
The initial letter of 'discuss' is 'd'.
'd'+'it'+'her'='DITHER'
(Other definitions for dither that I've seen before include "indecision" , "Faff about" , "trembling condition" , "State of high agitation" , "Vacillate, be indecisive" .)