Is helping others is obligatory in islam

Assalam alaikum ,I came across one statement., Imam Ja'far as-Sadiq (a.s.) says: "He is not a believer who inspite of being capable avoids helping his brother in need; Allah also leaves him on his own and does not help him in this world nor the Hereafter." And also Allah does not help a believer who does not help his brother in faith and leaves him on his own. Is this true ... Will allah leave me just like that.. if I didn't help... Because when I came to know this verse I lost my faith totally.. and cant able to make dua becoz thinking that allah will not help me ,also I can't able to make tawba for that .. knowing it's optional .Sadaqah is optional right??.. pls help me .I can't focus on my studies properly and Fully by came to know this🥲