PLEASE HELP

I have this harmful and nasty habit that nobody knows of ,i haven't mentioned it to my docor or anyone else for that matter.5 years ago i gave birth to my youngest son and found that i wasn't loosing the baby fat ,so i instantly started purging and withing weeks i was ballemic.I no longer had control over the situation ,i had lost the weight that i wanted to loose but was still unsatisfied with my body ,i felt as though i could loose a few more pounds but the purging wasn't enoug. So i than dicovered another way to make the food pass by forcing myself to have bowle movements .I no longer purge but im finding it hard to brake this habit ,Can somebody please help..am i the only one that does this ?is there a name for this type of thing and how much harm is being done?