Its not democracy if we always end up with a government we did not elect.

From 1945 to 2010 (covered by the data I looked at), the great majority of people in the UK had to put up with a government they did not help elect.   Until 2010, Conservatives governed with between 39.2% and 49.7%, or an average of 44.9% of the total vote; Labour governed with 35-48% of the vote or an average of 43%.   See the charts below.

(Data from Richard Kimber's Political science resources http://www.politicsresources.net/)

I have included the parties "natural allies" in each case, eg: Northern Irish Unionists with the conservative figures though some supported the government and some did not.  So the percentages overstate the main party figures.  

The actual level of support in the country is of course much lower than these figures suggest for a number of reasons including:

1.  Non-voters.  At least some of these are protest votes, confirmed by those UKIP voters in the recent by-elections who had never ever voted before.  Those "plague on all your houses" citizens views should not be ignored when the electoral system realistically gives them no voice.

2.  Tactical voters.  Votes cast "to keep the other lot out" are not an endorsement of the policies of the winning candidate.
3.  All parties are themselves coalitions, no more so than the "Red" and Blue", which means that a significant number of people voted for them who did not support all of their policies, and if they had had an alternative would probably have voted elsewhere.  

If you were to adjust for these categories alone, then I guess that the actual %age level of support for all the policies followed by the ruling party would be between 10 - 20% less than the national figures suggest.   That could be as little as 20 - 30% of voters.   If pollsters have more information about this I would love to know.

In contrast, in 2010, the Conservative Lib-Dem coalition brought together two blocks with a total of 60% of the votes cast.  The government is of course dominated by the Tories, for which many voters seem determined to punish the Lib-Dems, but pure Tory policy has been mitigated as a result.  That many Lib-Dems do not like some Tory policy initiatives, and some Tories do not like Lib-Dem initiatives is true, but is it any different from the situation within either of the two main parties which are themselves broad churches?  The rifts between Tory Euro-sceptics and pro-Europeans, or between New Labour and Clause 4 supporters, are as fundamental, if not more so, than the differences between Tory and Lib-Dem on some issues, but they were never an argument for punishing candidates at election time in the way that the electorate seem, as of today, to want to punish the Lib-Dems.

If you are looking for reasons for voter indifference and dissatisfaction with party politics in the UK today, then this is surely one reason.  To that can be added the effect of single member, first past the post systems where the vast majority of voters know that their vote will make no difference on polling day because theirs is a so-called "safe seat". The evidence to the contrary was clearly seen in the Scottish referendum where every vote had equal weight in the outcome.    

All this is a good argument for giving people the freedom to vote for a party that truly represents their opinions.  That does not mean a protest vote for UKIP, the Green Party or (in other times) Lib-Dems, It means we need proper proportional representation, preferably multi-member constituencies and  STV.  

In the meantime the fact is that there is good case for arguing that the current coalition government represents a broad swathe of middle-of-the-road opinion in the UK, and for the first time in the last 70 years the Tory-Lib Dem coalition has given us a government that represents the majority of those who voted in the election.  Furthermore, if a coalition is a likely outcome of the 2015 election, then it should be welcomed by the public for the same reason, even by people on the losing side.