Why do people come to me and open up about their problems only after knowing me for a little bit...

All of my friends and people I just meet often open up to me about their lives, problems, fears and often just need someone to talk to. I think I come off as a father figure in some ways, or maybe I am just an ear that will listen. It seems like girls right off the bat will tell me about their troubles or ambitions, and some guys will tell me their dreams and frustrations.