Who To Keep Close

I recently had a conversation with a friend who had been completely wronged in a professional situation and it got me thinking.  While I'm still fairly new to this city and trying to carve out my niche, I had to ask myself  if I was in over my head with the career I'd chosen and can I survive it here.  My friend handled her situation with such strength and grace, could I be as quick thinking and thick skinned if faced with the same challenges?  And when in a new place trying to build a business, how can you take the risks you need to succeed without really being sure of what you're doing? In this life, do you keep your friends or enemies close?