Wee creature abandoning a mate for life? (6)

I believe the answer is:

bestie

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'wee' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'creature abandoning a mate for life?' is the wordplay.
'creature' becomes 'beast' (synonyms).
'abandoning' suggests deleting specific letters.
'mate for life?' becomes 'ie' (I can't explain this - if you can you should believe this answer much more).
'beast' with 'a' removed is 'best'.
'best'+'ie'='BESTIE'

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I've seen this clue in The Telegraph.

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