Hey Claire

May I be blunt?  Are you a cutter?  Is this the self harm you are talking about? 

I do applaud you for reaching out and sharing this with people you care about.  I think it is something very hard for people to hear.  Do you think that your partner is scared over this and the only method he knows is to threaten to leave if you do it?  What sort of response would you like from him and others?  What helps you the most?

Are you in therapy at all?  I really think an objective voice here could really help.  Sometimes the people who love us just are not sure what to do. 

Ultimately you need another method to get that release.  Can you transform the self harm into something else to put all that energy into?  Think about what other ways you can get what you need to get through the bad times.

I think this is going to take a lot of work as well as time.  You may have to have many talks with your partner about what helps and what doesn't.  Give him something to do to help you.

I am sorry you are going through this.  It is so hard to break free of something which you begin to rely upon despite the harm it causes.  I do understand.

Please do let us know how you are doing in the weeks to come.  And thank you for your question.