It is not acceptable to be fobbed off like this. If you booked a combined flight and hotel you should be protected.
You should in that case get a refund of unused hotel etc.
you should have been given the option of canx. Your trip and getting a refund.
Did BA offer to re-book you on another airline?
weather can slow down the arrival and departure rate at Heathrow, so the fact that other flights were departing is not evidence that weather was not the cause of the delay.
Did you pay by credit card? If so, file a dispute with them, too.
Did you have any travel insurance?
It is also possible that you could claim under the EU regulations.
Have a read of the EU regs. Thread.