Someone experienced and supporting former husband (3,4)
I believe the answer is:
old hand
'someone' is the definition.
(old hand is a kind of someone)
'experienced and supporting former husband' is the wordplay.
'experienced' becomes 'old' ('old' can be similar in meaning to 'experienced').
'supporting' is a charade indicator (letters next to each other) (in a down clue, some letters go below others).
'former husband' becomes 'h' (I am not sure about the 'former' bit.**).
'and' after 'h' is 'hand'.
'old'+'hand'='OLD HAND'
Can you help me to learn more?
(Other definitions for old hand that I've seen before include "Experienced or practised person - manually aged?" , "expert?" , "Gothic script" , "master" , "Experience or well-practised person" .)