"Honesty makes you vulnerable."
What are you passionate about? What drives you? What do you think is your biggest flaw? What is one thing that you really like about yourself? What do you look for in a friend?—what draws you to people? Do you feel like you’ve really accomplished some(any)thing yet? Are there any defining moments from your childhood that explain why you are the way you are, now? What honestly scares you?
Thought of it?
Now share it. With someone you trust. It's good to have a soundboard, someone who can listen and help you know yourself more. But, don't let circumstances determine who you trust.
Because they're your roommate doesn't earn them the right. Because they are in the same club, group, or family as you doesn't earn them the right. Vulnerability requires some of your greatest strength, so don't waste it on anyone you're even a little bit uncertain about.
It's good to be open and honest. Who are you going to be vulnerable with? It's a difficult question, but a rewarding answer when it's not based off only circumstance.