It depends on who I'm dealing with. If I'm paying the person - like a doctor or whatever - I tell them right off the bat. Otherwise, I don't tell anyone anything.

The situation you described with your colleague - I would never get that close to someone. I've heard it said about me on more than one occasion, "still water runs deep." I simply never discuss my personal life.

Job interviews - first of all, are horrible. I don't lie, but I will shift the question if I need to. The question you were asked, about integrating into a team, I would say that I tend not to take a leadership role, but that I always pull my weight, and I jump in to help my teammates whenever they ask for help, and that the project is more important to me than being recognized for my individual contributions to it. Which is a nice way to say I would be a good worker bee.