Stop voting for the same two parties if they keep letting you down. Seems ridiculous to complain the government is doing x & y, and then vote them in again.

I don't think it is that simple. The usual option to the two party candidates is an extremest or more likely a one trick idiot appealing to some sub group of idiots. When there are reasonable candidates I have voted for them. They don't win.

Even if they did, the thing that seems ridiculous to me that I can't complain about something so complicated as a human being running something so complicated as a country. I did not vote for someone because I agreed with every little thing they said or stood for. I voted for them because I agreed with more of what they said than the others. I don't see how this precludes my protest or complaint when the candidate I voted for does something I disagree with.