Possibly a hellebore,the christmas rose.
Its a difficult time of the year to guarantee flowers of any sort in a garden.
There are shrubs like Viburnum dawn that have sweetly scented pinky white flowers but you couldn't guarantee it.
How about something like the hollies in the garden, they come into their own at that time of year
and maybe a christmas cactus for the house which with care could give you beautiful pink flowers in december......I,d wait until then to buy it as the garden centers will have plenty and you can choose the colour you like

Hellebores are beautiful but as Pamg says, you can't guarantee them that early. Up here they usually don't bloom until February. It largely depends on your micro-climate.

Maybe a carpet of snowdrops Heidi or plant hyacinths in pots both pink & white. Also winter jasmine but that is yellow. Pampas grass has large fluffy plumes, white or pink.
Virburnam bodnantense, flowers early too with both pink & white blossom.
Narcissus, white flowers would come up in the spring and be a nice memory after a long winter.
Some prunus autumnalis rosea, trees flower during the winter, i have one and the blossom is pink and delicate. I do hope you find something for your memorial garden.

fatsia does or false caster oil plant but im guessing you want pretty flowers of which these arnt peticulerly thow the plants evergreen and looks quit tropical .

Just remembered when looking at it that my Clematis armandii is always in flower just before Christmas, Heidi. Don't know if you want to consider a climber, and it does take 2 or 3 years to fully establish, but it's flowers are white and it is evergreen. That is if you have enough room.

Thank you all, will be googling all these and yes, maybe wait till the garden centres have stock...

your more than welcome x x .