Arthashastra
कृत प्रयासं मान्यं वा मोहान् मित्रम् अमानितम् । मानितं वा न सदृशं शक्तितो वा निवारितम् ॥
A friend who is neglected owing to inability to retain his friendship; and a friend who has become an enemy in spite of his ally's entreaties to the contrary;--such friends are hardly acquired; and if acquired at all, they turn away.
english translation
kRta prayAsaM mAnyaM vA mohAn mitram amAnitam । mAnitaM vA na sadRzaM zaktito vA nivAritam ॥
hk transliteration by Sanscript