What Michelle says makes alot of sense. Self-harm is always going to hurt those around us no matter how we look at it. I guess you have to make the decision if you want to quit self harm for you or for him. Ultimately for it to be more of success you have to do it because you want to not because you feel you are being forced into it.
Also if you are serious about giving it up it is important to look at the reasons behind your self-harm and then find someone such as a counsellor to begin to work through these issues with. As well as this it is also important to come up with healthier coping mechanisms because without them it is going to be hard to give up self-harm. You may also find it helpful to look at
this article on self-help for giving up self-harm.
You may also find it helpful to show your boyfriend
this article, so he understands that self-harm is not something you can just stop overnight. Lastly however I think it is important for him to also see that it is something that you want to stop and are taking steps towards this such as seeing a counsellor etc. Hope some of this helps.
Kat xxx