i have found for me that i started with self harm i would hurt my self when i was hurting so much i had to release the pressure. some how for me i traded the scars for eating till i hurt then purge to release the pain and the fear of all the calories at once but since i have stopped cutting i now purge more. cutting fells to me more like an impulse it feels good and hurts and is quick. and purging is more like beating myself long and painful almost all day long.