I don't know what your family situation is, but I'm pretty sure you'd never be a burden, and its thought like that, that are stopping you from calling out for help. You need to tell somebody, even if you haven't done it in five days, you need some sort of support system that can be there for you just in case you fall. This is after all what family and friends are there for, they are our rocks. What was it that made you stop last time? Think back to that time and how you got out of it. Because you can't let yourself fall back into this trap, no matter how strong the urge is. This is why I'm urging you to tell someone, who can help you, because you might not be able to do this alone.
We all have little relapses in our life, with any situation, but we have to get on with things and pick ourselves up from the ground and address any issues going on in our life, if we don't treat the cause of the problem, we are only going to find ourself in trouble again.
But at the same time, we can't let relapses be an excuse for getting back into bad old habits, it what our haters would love to see us do, fail. We have to prove everybody wrong and prove to ourselves that we are strong enough to pick ourselves up from the ground despite anything.
You might feel like right now that it could be so easy to fall back into bulimia, it might be easy, but its consequences are going to be alot harder to deal with. Is it really worth all the hurt and the pain? This is why you need to consider telling someone, because if you make yourself ill then your going to be more of a burden then than you are going to be right now.
If you don't feel like talking to anybody right now, find somebody online to talk to, because sometimes we can be our own worst enemy and put words into our heads like "fat" and "ugly", which I can assure you, you are not.
Don't go through this on your own, let someone help you, even if you think you have come through it this time, I'm sure you could use somebody to talk to about all the pain you have experienced this summer.
Things will get better if you give them time, stay strong and find someone to talk to, its obvious you want help, otherwise you wouldn't have posted on this forum.