There will be a feeling of understanding and interest between you, but you'll have to forcibly steer yourself away from playing armchair psychologist with this person if you want the friendship to be mutually beneficial! For some reason, you'll be almost too interested in their past. You two will spend a lot of time talking about your upbringings, your experiences with love and friends, and your theories on your own emotional makeup.
That's a great way to get to know each other at first, but it could actually impede any forward movement in this person's life if you're too focused on their past. What happened in the past is important; that's undeniable. But it's where you are now as individuals and where you're going in your lives that's the most important thing. If you pull them backward too much, you'll create an undue focus on what has already been, and not enough emphasis will be placed on what's up ahead.