Look, I understand the frustration at first. Life is a series of 'choosing the lesser of two evils' it's just that sometimes (rarely) we have the pleasure of the lesser evil being genuinely great if not phenomenal, rather than just better than the other.
So, you are sitting there complaining that you have to choose the lesser evil in an election and refusing to vote the lesser evil based on that... I mean, I at least respect the people who do truly vote for their third party 'throwaway' vote more than those who refuse to vote at all. I'm not here to virtue signal about voting, it's totally up to you what you do with your vote in an election but what I can say is that I personally will never not vote in a general election so long as I am a citizen of a country where votes aren't rigged and am entitled to vote.
Of course it's not just about your sole vote, if you can convince just 2 people to vote for the decisions you see as optimal for your nation and/or local seat/region then do so. Regardless, if you want to be private about your political views and not convince anyone at least vote, yourself. Trump won 2016 by targeted social media manipulation and even targeted letters to convince people not to vote for either party, who were likely to vote for Clinton. It has been exposed that Republicans are attempting something similar this time around as well, potentially:
Whether or not this is the case, please bear in mind that these dirty tactics only work because of an underlying willingness in people to refuse to vote for the lesser evil. What exactly is your endgame in refusing to vote? Do you think you will overhaul the system and neither party will win? All you have done is made it easier for the party you want least to win, to actually gain the victory. This ironically make you even more disheartened with the political system and more likely not to vote, people are voting less and less because of this strategy of manipulating you into complacancy. Do not be complacent.
Whichever party you support the least and who is likeliest to win, it is not a toxic reason to base a vote for the other major party, especially if you overall don't mind the other party winning. Choosing the lesser evil doesn't make you a morally less in-tact person, it makes you unwilling to cower out of a tough decision and that bleeds moral integrity in all ways.