Here are a few things I've learned about supporting a loved one with mental health issues:
Anyone can suffer from depression. A person with depression could be your neighbor, your best friend, your child's teacher, your pastor, your partner. It can be you. Depression doesn't play favorites.
Someone who has depression may not appear to have it. It doesn't matter how positive, optimistic, "together" they are. They can still suffer from depression. You could be a politician, a steel worker, a homemaker, a professor, an actor and be depressed. Often people with depression hide their distress and can hide it well. Your outgoing, bubbly friend who is always up for going out and having fun could easily suffer from it, and your melancholy, introverted teacher may not.
Your well-meaning advice may not help in a moment of deep depression. Your intentions are good, but someone who is depressed is driven by pure emotion. Whether or not those feelings are reasonable is a moot point. Their feelings are very real and very painful.
If you want to help someone one with depression, don't tell them what to do, but ask them how they feel. Never tell them that they shouldn't feel that way, or reason with them about why they shouldn't. Acknowledge their feelings. and love the person outwardly.
Put your love into action by helping with the things that are overwhelming them. Make a dessert or meal, help with housework, send a card, text or check in on them regularly. There are many things you can do, great and small. Saying you love them and support them but not actually putting that love into action is meaningless. Words are bullshit. Sorry, but they are. If you won't actually do something (and there's plenty you can do regardless of distance and money to show support) then don't bother with the words. It's just painful and counterproductive. That's not to say you can't reach out regularly with love and encouragement, but an occasional "I support you and love you" is absolutely meaningless when that's all you offer on the rare occasion.
A person who suffers from depression struggles to do the things they know they need to do. From small things like taking a shower, to bigger things like go to work or care for their children/pets/home. Tackling the task of getting out of bed and brushing one's teeth may be so overwhelming the person is incapable of doing it or uses every bit of physical and emotional energy they have to do it. If they are able to dig deep within themselves and manage to do the basics of daily life, they get drained. Then they feel so depleted that doing anything else is impossible. Going to the grocery store and taking care of their home becomes insurmountable. There will be times they can't be in public, or outside of their comfort zone without great anxiety and or absolute exhaustion. Sometimes they won't even be able to leave the house. They may not even be able to ask for help, even though they want and need it.
Don't take it personally if your loved one breaks plans or doesn't stay in touch the way you'd like. That day they cancelled on you might have been the day they barely managed to get up, get ready for work, resist the deep urge to wrap their car around a tree, and carry through their day without losing their calm in front of their coworkers, and they simply have nothing left to give by the end of the day. It also might be the day that they need someone there with them or an outward show of love,
If a loved one reaches out and shares their struggle, recognize this was probably a really hard thing for them to do. No one wants to feel like a burden, or to be that "negative Nancy". No one wants to feel like they're imposing on another person's happiness. No one wants to bring others down. Reaching out might just be the bravest and most difficult thing that person could do. Honor that. Don't respond with "well let me know when you're better so we can get together" or "you should just CHOOSE to be happy!" Or "you need to learn to stand on your own two feet". I promise you, that person will never, ever reach out to you again and they will feel as if they've lost a lifeline.
The guilt and shame and embarrassment people feel are real. It is terribly hard for a person who is depressed to allow others to see this part of them. If they share this deep part of themselves with you, let them know that having depression is nothing to be ashamed or embarrassed about. They have trusted you with a very fragile part of themselves. Don't destroy it by minimizing their pain or joking about it. Mental illness is not funny.
A person suffering from depression feels worthless. Unloved. They may KNOW that's not the case but that's not how they FEEL. The most common thing for their loved ones to say is, "you know I love and support you!" Again, in a state of deep depression, a person can know these things, but their feelings are driving them and unless they are being shown that love, knowing it exists on some other plane is meaningless. These feelings need to be responded to not with logic/reason, but with the most basic of things: love put into action. It might be just the thing that pulls them through.
A person suffering likely can't tell you what they need at the moment. The pain and feelings of isolation and worthlessness feel permanent, and they feel like they're drowning. Just like you wouldn't ask an actual drowning victim how you can help, don't ask a depressed person what you can do. Jump in. DO something. Saying "I'm bringing you by some dinner" is more powerful than saying "can I bring you by some dinner?" Declining help that is offered is much easier than asking for things.
Here are some links and resources to help friends and family of people suffering from depression and other mental health issues. National Alliance on Mental Illness, Help for Friends and Family Members of People with Depression,
There are many resources out there for family members and loved ones of those suffering from mental Heath issues as well. It's important to take care of yourself, too- be sure not to allow caring for another to negatively affect your health.