I self-harm also, but I could never do suicide because I know how it would effect my family and friends, and I'm not one to take the easy option.
Try watching this, I did, when i was thinking about suicide, and I was in tears. That's what I get for having a good imagination I guess:
I still self-harm, but a few times when I've really wanted to cut, I've written down everything I'm thinking about, no matter how horrible or pathetic it sounds. A few times, it's really helped and stopped me from cutting. I don't show anyone what I write, but it helps because I can see what I'm thinking and feeling, because it's there on the paper in front of me, and it's not just hurtful jumbled thoughts in my head.
You can message me on my youtube account anytime if you need to talk to someone (My youtube account name is 'FuckingPhsyco' XD) You don't have to tell anyone, but if you think talking about it would help, I'd tell your psychologist, because they're not likely to tell anyone.
Hope this helped ♥