egor, there ARE techniques.
this is what helped me SO often in these situations:
I just look at the clock, and remember, that no matter what happens, whether do I like it or not, time is still going to be automatic and will not ever stop. Whatever I do, whatever happens to me, whatever happens around me, tomorow will automatically BE, and will automatically pass. There is no way known to man to possibly escape tomorrow. Most importantly: you will automatically get through tomorrow, and will automaticaly get through this year. You will always get through, just like you did yesturday and the day before and the day before.
Of course sometimes the reason itself for your horrible feeling is that you don't HAVE ENOUGH time. You feel like you have no time to think through exactly how is it BEST for you to get through. and you go suisidal believing that it's the only way to escape time. But you gotta realize - if you kill yourself, you will NEVER get through it. And in fact, not only will you not get through this one problem (which could be completely irrelevant to the rest of your life in the first place) but you will nevre have another chance at effecting the world much more. You won't be able to change the way your friends think. You won't be able to change people's oppinions, can't help them anymore. Not just people, can't help the world anymore. Can't harm the world either. You might say "F*** THE WORLD!". But deep in your mind, you know that convincing people of stuff, and giving them your oppinion and in general changing other people might just be one of the reasons to live. Time will not stop, but you will no longer even exist to recognize the fact. And besides - there is absolutely no guerantee that heaven exists, and even if you're a strong believer you probably remember the many times you heard of suiside as being one of the worst sins.
You might be saying : "I don't even WANT to go through my problem, I simply want to get over with it!". But, you surely can get through it. You might not realize it, but as I said before, you will automatically get through it because of time, and if you want to get through it in a good way, you can surely achieve that as well - if you only decide to fight till the end and do everything you can possibly do to still get the best outcome out of your situation, you will only feel stronger and more satisfied. I say it feels great when you are absolutely sure you CAN't get through it, but you have this feeling that you're completely nuts and still going to. ( every time I felt that way, I got through all my troubles better than I expected and loved the feeling when it finally WAS over)
As michael said - most people that tried to suiside and survived usually love to feel alive after the the event and are very happy that they have managed to survive it. If you're not that kind of person and want to die even more after failing an attempt, please again realize the couple of facts I stated above.
You are very lucky to have such a friend that would comfort you to that extent. Friends are great, really really talk to her often about your feelings. It seems to me like you're in close relationships with her and can surely trust the person. Friends save lives, egor, friends save lives.
The last thing you should do is go to a doctor saying "I'm crazy, want to kil myself, please help", because they will take it very seriously and you might regret it.
As some other people said - exersise. And exersise as viciously as you like. It's a lot better to hurt yourself trying to punch a tree to death than to kill yourself.
Here's a story:
I still got that buckeye tree growing beside my house. I tell yeh, It's sooo cool to have the bruise on your knuckle and another on the right leg! The bark on the buckeye had long healed and too left an everlasting mark on it that grows wider every year as the tree grows yet older. I find very pleasing to look at from time to time. I fell in love with the tree ever since that day it probably saved my life. I'm growing one of it's seeds too. still haven't planted it back outside, it's growing taller every year inside a giant pot in my room. The funny thing is - we share a birthday with it. It started growing at my birthday a few years back just barely pushing a sign of green out of the nut.
But anyway, hope I helped.