My therapist once equated cutting to an addiction. As with any addiction, some people can quit and stay clean on their own, but most need continuing help and support. And as with addiction, you don't necessarily need a doctor as much as you just may need a support group to open up to. Certainly worth looking in to.
Also, did you stop therapy because you needed to for financial or other external reasons, or did you think you were no longer in need at the time? If you can, you really should get back in.

Good luck