Which is better in this era: isolation or intermingling? And how do we reconcile a good relationship with people with enjoining good and forbidding evil if we choose intermingling, or how do we endure loneliness and solitude if we choose isolation?

Sometimes isolation is preferred, and other times mixing with people is preferred. Where mixing is legislated, the Muslim must enjoin good and forbid evil with gentleness and leniency. He will not be harmed by people's anger if he acts in accordance with the Sharia (definition) when dealing with them. If isolation is better, he should seek comfort in Allah, frequently remember Him, and compensate for the absence of human interaction and the corruption of mixing with people by communing with Him.