Hello, I'm new and I've read some of your postings. I feel that you people can really understand me

I've been struggling with my ED for about 8 years now. I'm 20 and I've been anorexic for 6 years. Then I started throwing up, first I only purged the low-calorie-food I had been eating. But in january I moved out and I became a bulimic. Every day I bought large amounts of food and binged and purged all day long. I gained a lot of weight, I'm so unhappy and I want to stop - but it's so hard! Every day I do the shopping and every day I HAVE to buy these things like sweets, pizza, McDonalds food and so on. I hate myself SO MUCH for doing it!
I've made a poster and I mark every day I make without bulimia. I want to make it 100 days, if I make it, I will buy two cats, because then I have enough money to buy their food. But after three or four days, I always give up and binge again. I feel that I will never make it - I'm going to a therapy but it doesn't help very much - is there any way out? Today I start again with my healthy-eating-plans - for how long?
I want to study in October, I have to stop it, otherwise I won't be able to concentrate on my subjects. I'm so afraid I'll never make it!