Protecting your project when you're creating is imperative. It's amazing how random people (and those close to you) can mortally damage an idea by an off hand comment if you haven't learned how to protect your baby. I've had several projects that I had to shelve because I hadn't yet learned to how to keep them safe. I still occasionally have a twinge when an arrow comes from an unexpected person though they no longer kill off an idea, but I might have to take a few days to shake the comment off before I can get back to that bright and shiny creation.
I've gotten to the point that if I'm actively writing something I don't even refer to it by it's title. If someone asks what I'm working on I'll be as evasive as possible, referring to one project as my YA fantasy and another as a space opera. Most people, those casually inquiring, will just nod and move onto another area of conversation. Closer friends or those who seem to want to ferret out if you really are a writer, LOL, may probe deaper asking what it's about. That's where it gets tricky. This is when their reactions can affect how you personally feel about your baby. I know some writers that just give the answer that they don't talk about what they're writing about because the energy for it evaporates (or some other excuse). I've done this one myself, but sometimes you might be talking with someone who for whatever reason you feel the need to give them at least the basics. One trick I've learned is the Hollywood answer. I'll say 'It's like Star Wars and Pirates of the Carribean.'
What do you do to protect the creative energy you need for what you're currently working on?