Alright, so you feel a huge amount of release from stress when you cut, and you've lost blood to the point that you feel lightheaded. Ok, it sounds like you've got a severe self-injury disorder. Obviously the best thing to do is to call up a psychology clinic and speak to a registered psychologist about this, but I know that's a lot easier said than done.
Next time you feel like cutting, instead of trying to release the stress, calm the stress/overwhelmed feeling. There's a difference, trust me. If you only look for alternative ways to release the stress, you'll still have that addiction to instant release. Instead of going that rout, why not try slowing easing the frustration away until instead of smashed, it's lowered with ease?
When you were younger, did you do something creative when you were stressed? That's something most people seem to have the natural ability to do when really young but they forget as they grow older. If you're a good artist, draw something that'll express your feelings. If you like to write, write down how you feel. You'll probably draw/write really violent things at first and have to fight the urge to cut, but since they're peaceful activities you'll find yourself slowly feeling less and less stressed. After about twenty minutes you should feel better and you'll feel good about yourself for not cutting.
This can seriously work and it has for tons of people, but you have to seriously try. CHALLANGE yourself not to cut and you can stop.
You shouldn't have to feel suffering to feel released from bad emotions, and you shouldn't need to feel numb from emotion either. There are happy emotions too! Make it a goal to get there, please.
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