Some tips to help you be supportive when a friend or loved one contacts you and tells you they are sad or upset. This message could be of vital importance, because while 99.99% of the time it is just a bump in the road of life, there is always that 0.01% chance they are calling you while sitting staring down the barrel of a 9mm. Also, for the record, I'm not a counselor or mental health professional, just someone who has eyeballed that pillbottle and slit my wrists several too many times.
First off, recognize their trust in you. The very first thing to say is something like, "thanks for calling me", "I'm glad you thought to call me," "thanks for reaching out. That took courage," or "I'm so glad you trust me enough to talk to me about this."
If you are busy, say so. It is better to say it right out rather than divide your attention so you don't give the impression they are not really that important to you. It is okay to give a time limit.
"I'm really busy right now, but I can give you five/ten minutes if you want to tell me what's up."
You can always arrange for a callback time if you don't finish addressing their issue at the end of the time limit.
"Wow, sounds like we have a lot to discuss. I wish I wasn't so busy right now. I'd really like to talk to you about this. Why don't I call you at (name a definitive time)? Will you be free then?"
It is unwise to say, "lemme call you when I'm free". A person who is at the end of their rope is going be disheartened at something so nebulous. And, for the love of love, CALL THEM BACK AT THE APPROPRIATE TIME NO MATTER WHAT!! That's what alarms on your phone are for. Even my cheapo phone has an alarm clock with a 15 minute reminder beep, so I can wind down what I'm doing if I need to call someone back. If you find you are still busy, call them back anyway, talk for a few more minutes, addressing the fact that you didn't get free like you wanted and arrange yet another callback time.
DO NOT SAY "Don't worry. It'll be alright." Telling someone "don't worry" or "don't be sad" negates their feelings that they are trying to express. If the situation merits, saying "I'd be scared/sad/worried also" is fine. Telling someone "it'll be okay" is predicting the future, which you can't do and makes your other words of support seem suspect i.e. "this person really doesn't know anything about my situation or they wouldn't say that, why did I even bother calling them".
SHOW SUPPORT. Good things to say include, "I'm always here for you", "is there anything I can do to help" (often listening intently is plenty), "do you have any thoughts about what you can do to make this better?" and "what can we do together that might make you feel better?"
It is better to ask your friend their ideas, rather than submitting your own. If the person on the other end of the line is in a negative mood, they are probably going to shoot down anything you suggest as stupid or impossible. However, encouraging them to come up with their own ideas and then helping them implement those ideas both shows your love and support and has a much better chance or being successful. People do best when they have control over their own lives; rather than you telling them what to do (even if they do agree). And you improve the other person's ability to emotionally problem-solve by themselves, which is an incredibly useful skill.
If they absolutely cannot come up with any ideas despite your support and encouragement, suggest that you both do some research and look into it together. You can troll the internet while on the phone or you can arrange a time to meet them and look together, or you can both agree to do some individual research and have a contact time when you can go over ideas (this is great if you are chatting online long distance and can't actually see them in person).
There is some debate on whether or not you should call 911 on them if you feel they are suicidal. Lots of places say you should, but I've had this happen before and in my experience it always ends badly. As emergency psychiatric stays are usually around 48 hours, I can hide my suicidal thoughts long enough to get out (i.e. my friend just overreacted, I'm fine) and then go on to make the attempt. It also means I won't call that person again for any problems.
A better suggestion, if you feel the person is in imminent danger, is to have them agree to let you call. "I'm really worried about you. Do you think taking a break would help you gain some perspective? Would you consider checking into the hospital for me, just for a couple of days?" Sometimes, what people won't or can't do for themselves, they will do for you, so it's really good to add in "for me" somehow, as in "I'd feel a whole lot better if you did this for me".
At the end of the day, I've always taken the controversial stance that suicide is a personal decision that should not be taken away from someone. However, it doesn't hurt to take a few days to consider it. One of the great phrases that works well with someone who admits to being suicidal (and please don't assume they are no matter how sad unless they openly talk about this) is, "well if you really feel that way, taking a few days to think about this isn't going to hurt. You can always kill yourself in a couple of days if you haven't changed your mind, but you can't bring yourself back to life." As a last resort, that has been known to get people into the hospital when other words have failed.
Take care of yourselves, and take care of those you love!