Bhagavad Gita Chapter 1 Sloka 26 (1.26)

ತತ್ರಾಪಶ್ಯತ್ ಸ್ಥಿತಾನ್ ಪಾರ್ಥಃ ಪಿತೄನಥ ಪಿತಾಮಹಾನ್ ।
ಆಚಾರ್ಯಾನ್ಮಾತುಲಾನ್ ಭ್ರಾತೄನ್ ಪುತ್ರಾನ್ ಪೌತ್ರಾನ್ ಸಖೀಂಸ್ತಥಾ ॥೨೬॥
tatrāpaśyat sthitān pārthaḥ pitṝnatha pitāmahān |
ācāryānmātulān bhrātṝn putrān pautrān sakhīṃstathā ||26||
Sloka 1:26
Gist of the sloka:
At position where the chariot was parked, Arjuna could see, within the armies of both sides, people who were equivalent of his father, grandfathers, teachers, maternal uncles, brothers, sons, grandsons, friends, and his father-in-law and well-wishers.
Explanation:
Arjuna for the first time in the battlefield realizes that his own people who were equivalent of his father, grandfathers, teachers, maternal uncles, brothers, sons, grandsons, friends, and his father-in-law and well-wishers – are all present for the war.
Until now Arjuna, who was confident about his capability, now realized the full extent of the war. Its destructive capability which could take down the lives and arms of his near relatives. Some of them he might never see them alive, post the war. The psychological impact of this was fully felt by Arjuna and his subsequent words indicate the same.
In a way, Lord Krishna wanted to give a shock treatment to Arjuna to set him up for psychotherapy.
Please note that while there were many more non-relatives than relatives/friends, Arjuna only saw those who were known to him directly. He ignored those others who were also put into similar situation of fighting a war and probably losing their lives. As a Kshatriya, he showed his weakness for his relatives/friends when he should have treated all as equals.