I want to vote green.
People are saying this is likely to take away votes from labour, and that it may well be that the greens might even loose brighton and thus have no seats.
Therefore I am worried that if I vote for who I want to vote for (greens), that it will result in something more horrible (con/ukip) than voting for something that I don't really want(lab/lib), but its something that isnt as bad as something else which might get in if i vote green.

Without arguing about the actual flavour of politics.

Can someone please explain to me whether this is a 'democratic' thing?
or is it a 'flaw of the form of democracy that we have' thing.

Also, given that the voting system is not going to change to reflect how I feel (seeing as libdems decided to not go for proportional representation, even though they finally got in power)
How should someone in my position vote?
Should one vote sincerely? or should one take the inadequecies and faults of the representational system into account and just do the dirty thing?

If one does vote, then has one given their approval of the result, does it also give tacit approval to the method of representation? How does one register ones true feelings democratically?