I'm a woman in my 20s. Some stuff in my life was going really wrong, and I got depressed. I didn't tell people, but it had to be obvious. I distanced myself from my group of girlfriends, meaning I missed birthday parties, didn't respond to group texts, and was overall not a great friend. Still, I did what I could, like taking a friend for a spa day after missing her birthday the week before. Weeks later, I learned she was still harboring resentment that I had missed her birthday. Don't I deserve a bit of a break?

--Feeling Better Now

On the day of your friend's birthday, you felt like quite the party animal -- if, by "party animal," we mean "rat lying cold and dead in the corner of the cage."

Depression gets a bad rap. It can be a terrible, dysfunctional thing when it's caused by brain abnormalities or persists without end. However, psychiatrist Randolph Nesse explains that human emotions, including the feelbad ones, are psychological programs that evolved to solve recurring mating and survival issues. When you're mired in frustrating, unrewarding endeavors, symptoms of depression like sadness, hopelessness, and fatigue appear to have a function. They slow you down, plant you on the couch, and force you to rethink and change unworkable situations in your life: dump that jerk, stand up to your boss, fake your death and move to Croatia.

Sadness is also a strong social signal. When we see someone's sad, we're motivated to comfort them (or at least cut them some slack). In an ancestral environment, countless centuries before apartments with locking doors, your friends would have noticed you were depressed. In a modern environment, suffering often remains hidden. In other words, it's possible this woman and your other girlfriends assumed you were socially sloppy, inconsiderate, and a bad friend -- instead of understanding that you were a friend in need.

Take stock of the girlfriends around you and figure out whom you can trust to be real friends to you: those you can show who you really are, including all the sobby parts. Friends like that will mop up for you socially (in tactful ways) at times when your answer to, "Hi, how are you?" is likely to be: "Actually, I'm going to die alone, and then nobody will discover the body until the UPS guy comes to the wrong house and nearly keels over from the smell."

For pages and pages of "science-help" from me, buy my latest book, "Unf*ckology: A Field Guide to Living with Guts and Confidence." It lays out the PROCESS of transforming to live w/confidence.