Personal Stranger
Someone who will always stay a stranger to you, yet they help you go through some tough times and are always there to talk with you about anything. Most of the time these are either people you meet online or someone like a bartender.
"Hey man you ok? You seem kinda down"
"I'm fine thanks, i've talked with my personal stranger about everything already"
"I'm fine thanks, i've talked with my personal stranger about everything already"