Eat too much egg ourselves: it's lovely (8)
I believe the answer is:
gorgeous
'lovely' is the definition.
(I've seen this before)
'eat too much egg ourselves' is the wordplay.
'eat too much' becomes 'gorge' (I've seen this before).
'egg' becomes 'o' (an 'o' resembles an egg).
'ourselves' becomes 'us'.
'gorge'+'o'+'us'='GORGEOUS'
'it's' acts as a link.
(Other definitions for gorgeous that I've seen before include "Wonderful to taste or look at" , "delightful?" , "Showy" , "Richly coloured, magnificent" , "Stunning" .)