Stick with your true brothers
“Stick with your true brothers. You can live in comfort with them, as they are a delight in times of ease, and you can lean on them in times of hardship.
Assume the best about your brother until he comes with something that should alarm you from him. Avoid your enemy, and beware of befriending anyone but the trustworthy, and there is no trust for the one who doesn’t fear Allaah.
Do not befriend the corrupt, as he will teach you his corruption, and do not reveal your secrets to him, and only consult those who fear Allaah, the Exalted.”
— Umar Ibn Al-Khattab (radhiAllahu ‘anhu) [Mukhtasar Minhaj al-Qasidin of Ibn Qudamah, pg. 132]