If you look at it like this - last year i was working as a nurse, then i fell downstairs and broke my leg. On top of my other illness, it means that my mobility is poor. this meant that i couldn't always carry out my duties as a nurse. This was a genuine disability, not my fault etc, yet how can i still expect them to employ me as a nurse when i can't walk very far anymore?
In this situation, there was nothing they could do to make reasonable adjustments so that i could still do that job, and despite the fact the DDA applies to me, they were still within their rights to make me redundant, and its not discrimination ... i am patently unable to carry out the job i was employed to do. The same could be applied to you - if you are unpredictably and often unable to carry out your role, they would be within their rights to make you redundant