Srimad Bhagavatam Canto 11, Chapter 07, Text 52

SB 11.7.52

nati-snehah prasango va
 kartavyah kvapi kenacit
kurvan vindeta santapam
 kapota iva dina-dhih
One should never indulge in excessive affection or concern for anyone or anything; otherwise one will have to experience great suffering, just like the foolish pigeon.
The Sanskrit prefix ati, or “excessive,” indicates affection or attachment in which there is no Krsna consciousness. Lord Krsna says in Bhagavad-gita (5.29), suhrdam sarva-bhutanam: the Lord is the eternal well-wisher of every living being. The Lord is so affectionate that He sits in the heart of every conditioned soul and accompanies him throughout his endless wandering in the kingdom of maya, patiently waiting for the conditioned soul to come back home, back to Godhead. Thus the Lord makes all arrangements for the eternal happiness of every living entity. The best way for anyone to show compassion and affection for all living beings is to become a preacher on behalf of Lord Krsna and assist the Lord in reclaiming the fallen souls. If our affection or attachment for others is based on bodily sense gratification, in the name of society, friendship and love, that excessive, unwanted affection (ati-sneha) will cause burning pain at the time of the breaking or destruction of the relationship. Now the story of the foolish pigeon will be narrated. A similar story is described in the Seventh Canto, Second Chapter of Srimad-Bhagavatam, told by Yamaraja to the mourning widows of King Suyajña.
Srimad Bhagavatam Canto 11, Chapter 07, Text 51
Srimad Bhagavatam Canto 11, Chapter 07, Text 53