Discover former lover carrying ecstasy on a street in Seven Sisters area (4,6)

I believe the answer is:
east sussex
'discover former lover' is the definition.
I can't tell whether this definition defines the answer.
'ecstasy on a street in seven sisters area' is the wordplay.
'ecstasy' becomes 'E' (informal term for the drug).
'on' says to put letters next to each other (in a down clue, letters appear on others).
'street' becomes 'st' (abbreviation).
'in seven sisters area' becomes 'sussex' (I am not sure about this - if you are sure you should believe this answer much more).
'e'+'a'+'st'+'sussex'='EAST SUSSEX'
'carrying' acts as a link.
Can you help me to learn more?
(Other definitions for east sussex that I've seen before include "area that's down a lot" , "English Channel county" .)
