Orchids hate me

I love orchids, but I sadly have a habit of killing them. I blame the fact that they are tropical plants and its hard to replicate those conditions in Scotland. However my boyfriend has faith in me and bought me an orchid and I have named her Rigmor.

Like most pretty things, they are a little high-maintenance and a bit picky: they like light, but only north-facing (check); they hate draughts (check); and they only like soft water (check). Never, ever cut the aerial roots off (the slightly greying roots curling around the top) (check), and never, ever remove them from the original plastic pots they've been rooted in... (this may be where I have been going wrong)... Good Luck Rigmor.