ESA benefit help

[newey]

hi all,,,,, a little advice needed please
i broke my back in three places and fractured my neck, in 2008
i can still walk in a fashion but since then my sister looked after me
till she died in jan 2010,

i have never made a claim till march 2011

i met a women 6 month before my sister died and i moved in with her
since then we have been give the news that she has non-Hodgkin’s follicular lymphoma
terminal.

she put in a claim and was granted ESA at £99 a week under (Special Rules for terminal illness)
And was told by letter that this was the amount she was entitled to for herself as a terminally ill clamant

just after i made my claim for myself as she has three children and i could not expect her to pay for me to
and was granted ESA also at £4,22 per week which has now gone down to £2.74
when i asked why they said its a top up to benefits as we are classed as a couple

i would have thought as my partner is terminally ill and was granted her benefit under
the (Special Rules for her terminal illness)
this could not be linked to me

if this is correct it seems that her So-called (Special Rules for terminal illness) clam has gone out the window
or been ignored surly this cannot be correct

can anyone tell me thanks newey