Contented to leave with Lucy before the final weekend being very easy-going (5-2-5)
I believe the answer is:
happy-go-lucky
'easy-going' is the definition.
(I've seen this before)
'contented to leave with lucy before' is the wordplay.
'contented' becomes 'happy' (glad means contented or happy).
'to leave' becomes 'go' (to go is to depart or leave).
'with' says to put letters next to each other.
'lucy before' becomes 'lucky' (I can't justify this - if you can you should believe this answer much more).
'happy'+'go'+'lucky'='HAPPY-GO-LUCKY'
'the final weekend being very' acts as a link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for happy-go-lucky that I've seen before include "Carefree" , "Free and easy" , "Easy-going" , "Insouciant" , "Cheerfully irresponsible" .)