I think some people might flame me for this but i have been cutting for 14 years so i do have some idea of the ins and outs of it.....
Maybe, just maybe, you are not ready. When i was in a really bad way cutting-wise i wanted to stop, but i couldn't because i wasn't ready. And people pushed me to stop but i again, i wasn't ready. I didn't want to keep hurting myself but i had to deal with some of my problems before i could start on the journey of recovery.
Self harm is not just that. It comes from somewhere. And you gotta figure out where it comes from and what it gives you in order to be able to win the fight against it. It doesn't help to say you'll stop and then something happens and you need to harm and then you beat yourself up over not being able to resist. It takes a lot of time and a lot of therapy and a lot of getting to know yourself.
I think a lot of the kids around here would be better off if they could recognise that self harm is a bad thing but sometimes you need it for a while. It's with self harm as it is with many addictions, only a very few people can stop and go cold turkey. Most of us needs help and guidance along the way. And sometimes it's ok to recognise that you do hurt yourself but it's no use to beat yourself up every time you slip up. It just leads to more guilt, more frustration and in turn more self harm.
Maybe you are not ready to stop. Maybe you don't have the tools to make you stop. That is not failure. That's being human. It's ok to do something even if you wish you could just not do it. It takes a lot more than willpower to stop cutting and putting it behind you. And you already struggle enough as it is.
Try to think about what you'll need in order to stop. That's often the first step. Just sit down and think about it. And it's ok to need to help from others. It doesn't make you any less of a person. It shows courage
Best of luck with everything and i hope i haven't blabbered on and on for forever....