European gaining access to husband's love nest (7)
I believe the answer is:
slovene
'european' is the definition.
(someone from Slovenia)
'husband's love nest' is the wordplay.
'husband's' becomes 'sne' (I can't explain this - if you can you should believe this answer much more).
'nest' is an insertion indicator (nest' can mean to fit one object into another).
'sne' enclosing 'love' is 'SLOVENE'.
'gaining access to' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for slovene that I've seen before include "One from Ljubljana" , "Central European" , "Southern European" , "Language" , "Native of Ljubljana" .)