You might want to look into Buddhism for an inspiration on truth if you haven’t done so already. I’m definitely not saying that you should become a Buddhist, but it should be an interesting viewpoint.
Personally, I have never cared too much for truth in politics. You don’t win elections by being able to present more truths. You win by getting more people to vote for you. Some people lie, some people tell the truth, and other people lie and tell the truth to get votes. You don’t get bonus votes by telling truths and you don’t lose votes by telling lies. What I hope for, in candidates that I vote is that at least they can create laws that will be beneficial and work. Truth and honesty are optional. My opinion is not very popular but I choose live by it.