In situations like these, you need to find the root of your problem - find out what makes you feel the need to cut, then you can tackle the issue at hand. I can totally understand why you're scared of talking to your mum. It's a scary subject to bring up, especially to your parents. Is there anyone else that's not in your direct family that you could talk to? A family friend, for example. It's often easier to talk to someone who you don't live with and who you don't see all the time. Maybe that person could help you talk to your mum, and it won't be so scary for you to talk about it.

Perhaps once you've done that, and your mum knows, you could talk to her about getting you some professional help. The fact that you're ready to get help is a very good sign - it shows you really want to get better. Therapy is the first step along the road to getting better, so well done for taking that step :) A lot of people really struggle to do that.

Good luck! I know it's scary, but if you want this sorted, it's really worth overcoming those fears and really starting to tackle the problems you're having.

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oh, baby it's a wild word, and it's hard to get by just upon a smile
be the change you wish to see in the world

You mentioned you don't want to talk with your mom (*1)about it and although I think it could be very beneficial perhaps you should try to talk  with a friend, adult, school counselor (*2) just to start getting used to the idea of talking about it.

*1: I know that you're scared of telling your mom because she might be mad or something like that. It's not hard to admit we have problems, and that we're not perfect to our parents, but doing it takes lot's of courage and once you get it over with, it can only make the relationship with your mom stronger. Give her the chance to be there for you, she might surprise you. As your parents I'm sure she'll want to help you. Please even if it takes some time, you need to tell her because she lives with you. You're going to need as much support as possible to fix this, and she needs to pear of it. You care about her, maybe you don't want to hurt her.. but you could end up hurting her more by hurting yourself and not telling her. Just open up and go for it. Once you start things will get easier.

*2: School counselors are professionals who have studied and are there to help you. Just go and open up, he/she will try to find you the best options, and they can even help you to talk with your mom about it. Don't over think it, just go for it.

Take things little by little, baby steps until you can run!

I know it might be hard, but in order to progress you need to address the issue. You've already admitted that you need help, that's marvelous! It's probably the first step into getting better, but now you need to find somebody that can give you support, help and advice, somebody that knows how to deal with this type of things.. A professional! Your counselor, doctor, even your mom or yourself in the phone book can find somebody that knows about this things that could help you.

Find what's your trigger and try to avoid it, at least until you find the courage to tell somebody and start to get help! Remember, the sooner the better, just go for it!

You can learn more , get support, etc; here:
How to stop
Guide to self harm
Link 1
Link 2
Link 3

Good Luck, my inbox is open if you want to talk.

:)

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You'll never get to heaven if you are scared of getting high.