And the thoughts that occur in the mind of a person who is suffering from depression are very different than the flashes of annoyance felt by a healthy person. "Depression is caused by a chemical imbalance in the brain. It's not something that just goes away when circumstances are different," explains Dr Norman Sussman, a professor of psychiatry at New York University's Langone Medical Center. "And snapping out of it just doesn't work. It's like asking someone with a broken leg to walk. For people who suffer from depression, it's not a choice or a 'mood'." 

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To help understand what it's like, we spoke to real women about how depression feels for them. We've changed their names, and in exchange they've been as honest as possible. If you're not sure if what you're feeling is depression or just the blues, schedule an appointment with your doctor.

"I can't get out of bed."
"The phrase 'I can't get out of bed' is so common, but people don't get it: When I'm in a depressive phase, I literally can't get out of bed. My body feels like concrete. I don't even want to turn off my alarm, because even moving my arm just requires way too much energy and coordination." —Melissa, 25 

"What to wear today: rumpled shirt from the floor."
"I don't care what I look like. Nothing looks good in my mind, and even thinking about what to wear requires more brain capacity than I have. Sometimes I'll wear the same clothes 3 days in a row, even sleep in them, and it takes everything I have to get myself to shower." —Jane, 33 

"Everyone around me is thrilled to get an e-mail that there are free bagels in the office. Am I the only one who can't make myself care?"
"One of the worst things about depression, to me, is the isolation. I feel like I'm totally different from everyone around me. I feel like everyone has this whole range of emotions, and can be totally exuberant about something tiny, like free breakfast at work, while I just feel like a zombie." —Helen, 28

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"Why does my boss even invite me to these meetings? My contributions don't matter."
"I know, logically, that I matter to people in my life, that I'm a good wife, mum, friend, and coworker. But depression overrides that. It makes me feel useless, like I can't do anything right and that there's no point to anything I do." —Jen, 45 

"Two new text messages? Can't people leave me alone?"
"Isolation is a huge part of depression for me. At this point I have enough friends and family who know I've struggled with depression, but before I told people about it I seemed like a bad friend. I'd let messages pile up because, as odd as it sounds, I was physically incapable of responding. It felt like it took everything I had just to plod through the day; anything extra, including a 5-second text, was just way too hard." —Stacy, 37

"I feel so sorry for my partner. He didn't sign up for this. He would be so much happier with someone else."
"When I was at my lowest point, I was practically begging my husband to divorce me because I felt like I was a terrible wife and I was just dragging him down. Whenever I said that, of course he'd refute it, but nothing he said could get through to me. I truly felt like the worst wife in the world, and even telling him that made me feel worse because I felt like I was trying to manipulate him." —Sarah, 64 

"I can't go to happy hour. I need to huddle under the covers for the next 12 hours."
"I'm not sleeping, and I'm not watching Netflix. I'm just lying in bed feeling awful about everything. Sometimes I get panicky about things: I think of all the things I have to do and how I don't have energy to do it, or sometimes I'll just lie there and my mind will be blank. But not a good blank, like you sometimes feel during a massage or after a yoga class. Just this dull, empty, bored feeling that's impossible to escape." —Jessica, 33 

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"Dinner? No interest."
"Depression changed my eating habits so much. I'd either not want to eat, or I'd want to eat everything, by myself, standing alone in the kitchen with the fridge door open. But eating definitely wasn't pleasurable in any sense of the word." —Linda, 50 

"Don't touch me."
"Being touched by anyone felt awful; like, literally, my skin would prickle. Holidays were the worst; everyone wanted to hug and I felt like I had a big, blinking leave me alone sign above my head that no one paid attention to." —Beth, 42 

"I don't want to fall asleep, because I don't want to wake up."
"For me, the thing that stood out about depression was the sameness: I felt horrible all day, every day. My mind definitely went to some dark places. And I felt like there was no way out; every single day was another day of feeling the same. It wasn't until I saw a therapist and began taking medication that I began to realise that I wouldn't have to feel that way always, for the rest of my life." —Lindsey, 38

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