Hiya

I don't think you do need a kick, I think you need more kindness and I think you are being harsh on yourself to perform at a certain level all the time. No one can do that, everyone has good days and bad days. You are allowed too!
Lots of people go to work and can't function at normal levels.. they whinge about it, groan, stay at work and do half as much as usual but drink twice as much coffee, but still get paid. Then on another day they are back to normal again. It is okay to do this. It is human.
I've seen how kind you are to others.. and I don't think you would give a coworker a hard time for having a bad day, so why is it acceptable for someone else and not for you?
Also, I know how you are with everything you do.. so what you give with 50% is probably the same as someone else's best day!
"I can't allow myself to reveal weaknesses and failures to others. I leave the situation immediately to prevent the possibility of a frustrated sigh or negative comment being made towards me from another colleague."
Maybe if you let a few groans out from time to time it wouldn't build up to the point where you couldn't go on anymore. Because by keeping it all in and showing nothing at all that you have decided could possibly be seen as negative, the feelings you have that started off totally normal daily reactions that everyone has.. these grow and grow until they are monsters big enough to eat you in one bite.
"I'm okay when I'm the person who makes everyone in the office laugh and who works 50 hour weeks and takes on loads of responsibilities..... But being able to do all that exhausts me and when I feel I'm not able to cope I GO GO GO!"
How about being the worker who works 35-40 hour weeks every week. And on the good weeks you don't do extra so that when a bad week comes you can still pull through because you have that little bit extra energy?
"I don't want others to think I'm crap. I just don't have the self esteem for it."
You aren't crap. You are awesome. I think when we feel low about ourselves and we judge ourselves harshly we have the expectation that others will do the same. But most of the time that is not true. Usually people are harsh on themselves and kind to others. If someone ever is actually harsh to you then you don't have to care what they think anymore because they are not someone you want in your life anymore.
"It's why Im holding onto my anorexia. It makes me feel that at least I have this. It's like a possession almost. It's a protection from being rejected."
I don't know if you ever read The Prophet by Khalil Gibran. But there is one part of that story that has stayed with me since I first read it. The prophet can finally go home and that is what he wants.. but he is finding it hard to leave his pain behind because he has been living it for such a long time:
"Almustafa, the chosen and the beloved, who was a dawn onto his own day, had waited twelve years in the city of Orphalese for his ship that was to return and bear him back to the isle of his birth.
And in the twelfth year, on the seventh day of Ielool, the month of reaping, he climbed the hill without the city walls and looked seaward; and he beheld the ship coming with the mist.
Then the gates of his heart were flung open, and his joy flew far over the sea. And he closed his eyes and prayed in the silences of his soul.
But as he descended the hill, a sadness came upon him, and he thought in his heart:
How shall I go in peace and without sorrow? Nay, not without a wound in the spirit shall I leave this city.
Long were the days of pain I have spent within its walls, and long were the nights of aloneness; and who can depart from his pain and his aloneness without regret?
Too many fragments of the spirit have I scattered in these streets, and too many are the children of my longing that walk naked among these hills, and I cannot withdraw from them without a burden and an ache.
It is not a garment I cast off this day, but a skin that I tear with my own hands.
Nor is it a thought I leave behind me, but a heart made sweet with hunger and with thirst.
Yet I cannot tarry longer.
The sea that calls all things unto her calls me, and I must embark.
For to stay, though the hours burn in the night, is to freeze and crystallize and be bound in a mould.
Fain would I take with me all that is here. But how shall I?
A voice cannot carry the tongue and the lips that give it wings. Alone must it seek the ether.
And alone and without his nest shall the eagle fly across the sun."
Whenever I start to think about getting better or moving on in life.. this comes back into my mind. I thought maybe it would be something I could share with you.
You are making progress. Everything you are feeling is normal and acceptable. Just remember to be kind to yourself for all of it, who you were, are and will be.
Here is an interesting article in the Guardian over whether or not to disclose mental health issues at work:
https://www.theguardian.com/careers/car ... th-at-workFor me the key points were that it is always your choice. Maybe something to get some advice on from the CMHT or CAB or whoever you can talk these things through with.
And the point made there was:
"would you want to work for someone who does not understand – and refuses to entertain the idea of - an employee with a common health complaint?"
Your post was not moany, and even if it was that would also be okay!

We won't think bad of you here so you never have to worry about that again. Give yourself permission to feel how you feel. Because actually you don't have a choice so you are using a lot of energy wishing you felt another way when you can't. You can only decide what to do next. And for that you can trust your own instincts.
I'm sure you are going to have lots of good and bad days all mixed up for a long time. I am too and it is horrible swinging between feeling good and functioning and then crashing back down. But I am sure the answer for us both has something to do with accepting ourselves.