As much as the 'cheer up' and 'just smile' brigade are well intentioned unless your 100% sure of where someone is in their head it's probably not the best response. I will slap the next person who says it to me upside the head.
I don't want to hear about how so and so's life sucks worse or they're dealing with the same shit and coping and I'm being stupid, ridiculous. I will feel how I feel about stuff as it happens thank you and I won't be made feel guilty or apologize about it any more. I am fucking entitled to those feelings, to feel as is anyone else to their own. This is why I DON'T open up in real life and give my automated 'i'm good!' response in general because I was never, never allowed to be pissed off about anything, sad about anything it was always 'wise up' and 'but what about me' as they went on their very own rant and I stored away something else that I wanted, needed to say or wanted help with until time after time of the same damn thing every fibre inside my body screamed with the overload as the little mute mouse everyone expected carried on for all intents and purposes doing just dandy.
I, of course, can and do rationalize that the complete majority of people out there stuggle daily too with bills, work and other issues and they figure it out and they cope. But.... those things when your low, when you feel so sad and mind numbingly depressed, those things tower over you, they sit on your chest until you can't breath, everything makes you anxious, everything is scary and so are your coping mechanisims. And those things, they are not the cause, they are just another focus because for so many depression isn't about 'things' or an event. It just simply IS. I have lost count of the times I've been asked 'why' and I wish I had an answer, but honestly sometimes there just isn't and sometimes that has to be acceptable. If we knew we'd fix it right! What I know right now is that I hate going out, I ignore my phone too much because I don't feel like talking, that I can't cope with untidyness and feel so overwhelmed at the smallest thing out of place that I want to sob, become totally unmotivated to do anything then because it seems pointless if it's all going to be wrecked again in a minute and that last night because my flatmate closed my door on her way past, maybe because she wasn't digging what I was listening to, I felt soooo isolated and rejected that I did sob for quite a bit.
That's a little more than 'sad' and 'smile' won't cut it. Just take 2 seconds before you say it to really think about what place a friend or family member may be in before those words tumble out. I know it's maybe because you don't know what else to say, you can't know what's going on, your trying to be positive and help but yeah... I'll leave it at that.