Except this is exactly how our government is designed to operate - and has operated, for the most part successfully, throughout its history. Britain has only ever had three referendums. One (AV in 2011) turned out basically to be pointless, and 2016 has been disastrously oversimplistic. I can't really comment on 1975......
As a voter, you have to weigh up which are the most important issues for you, and then vote for the candidate that you think will represent your views on those issues the best.
If you don't like any of the candidates - that sucks. It's a risk. Then you've just got to hold your nose and vote for the least worst option. But again, that's representative democracy.
Yes, there's one issue that looms above all others right now.
But the reason we need a GE is because the government has been a shambles, and the opposition has been a shambles, and therefore it's beyond time that each and every MP stands up in front of their constituents and justifies their actions. A functional parliament, who can actually make a decision on Brexit, would hopefully be the result. If not, we'll still be in a mess, but at least we'll have tried out the one tried and trusted method of resolving bad government that we have available to us under our form of democracy.