I know what you´re talking about... especially if I skip meals my head is like "taken over" by ED-thoughts. I cannot give you advice because I need some myself - but you should know you´re not alone about this.
I would say that there are not 2 sides of 'you', but just one real you - the one wanting to get well, and let your Mum and tutors help you achieve that, and the other voice is not you at all, but the evil ED that has controlled and bullied you all this time, and taken so very much from you already.
I still have this too - the reasoning that says that at my new weight I am slim, and healthy and so much better off now, and the sickness that still tells me I'm fat, ugly, weak to have given in and gained... (you get the picture). The trick here is to use logic to silence the bad advice to yourself - to lie to people, and get sicker and sicker... and to work out your BMI/calorie intake/ or whatever, and see if it REALLY means you are indeed at a 'normal' weight, and eating a 'normal' amount of calories. No? If not, then the voice telling you to starve even more is a liar, out to kill you. I mean, it hasn't helped you in your career or life recently, has it?
Added to that, I am now going to shout very loud, to drown out the lying, death-wish voice:
GO BACK TO YOUR THERAPIST. LET YOUR MUM AND TUTORS HELP YOU. EAT WELL, AND GAIN TO A HEALTHY LEVEL, AND GET YOUR LIFE BACK!
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