when I was pretty depressed about a break up, heres what got me through. Talking to my mom was number one, but also think of it this way....somewhere in the world..someone has it way worse than you do. People are loosing parents, children...all kinds of stuff. You can probably even see questions on here about situations that are way worse than what your going through. This makes your situation not seem so bad....thats what helped me...

I used 2 cut my self ....I've even came close to suicide once ...just think about what your doing I know that you don't know me and I'm really not trying to do anything ..I'm just a teen who can't sleep so I'm on yahoo answers lol but just please if you need someone 2 talk 2 hears my email. Laffytaffyheav@yahoo.com

stop cutting. don't cut. nothing is wrong with you. there is something wrong with you backstabbing friend. friends are overrated. just keep the good ones. do something else to feel a rush instead of cutting. like smashing things or breaking things.

I have been cutting myself for 7 years now. I have recently stop.. only for about a month. Urges to cut are extremely strong. However, you're stronger. Fight them.

There's nothing wrong with you, it's your friend that messed up. It's a sad state of affairs when a friend you trusted turns out to be a rat, but they're not worth hurting yourself for.
There are support groups online to offer help. I don't know where you live, so can't say if there are any support groups in your area. Set backs can happen when you've had a period of not cutting, so don't be too hard on yourself. You know you have managed to find ways to cope without cutting, you will be able to again. You've proved it.
If you worried your best friend may start cutting if tell her bothered you will, you could try talking to her, tell about what happened with the other friend and tell her your upset and leave it at that. Your good friend may be only too pleased to give you support. That can only serve to make you both feel better

I'm sorry if I insult you...

The man side of me says stop being a girl and man up...

But the more sensitive part of me actually feels for you
I had friends that used to cut
They are all super chill dudes and chicks

The way I deal with friend issues is like this...

Friends come and go (Trust me even the really close ones)
Whether is by choice or some turn of events

You shouldn't be hurt by those who call themselves "friends"

She can live her life the way she wants to and it will not affect you in anyway

The only thing that will affect you is how you live YOUR life

Love yourself
don't let anyone try to pull you down

Only you can control that