Why is it a terrible reason?
I mean, Its not the only reason (trade policies, flip flopping, gun laws, past feelings towards video games, etc).
I'd say refusing to vote for these reasons shows how much you sincerely care about the big issues that Bernie tends to espouse - since you did mention that you're all about supporting candidates who promote progressive policies - but correct me if I'm wrong.
It's been mentioned more elegantly before, but when I read posts like this I can only picture armchair activists who are only a part of this as someway to feel like they're making difference, ultimately as a way of self-gratification. But then when it comes down to the wire - if the choice is really between Hillary Clinton and Trump - fuck the person who is going to pass most of what I support, because she gave speeches to big companies, received money from rich people, and evolved her position on some issues to agree with what I do now.
Fuck the issues that I claim to care about, because at the end of the day, I can afford to let equal rights for LGBT individuals go down the toilet. At the end of the day, I can afford to let laughing at climate science be an official government position. At the end of the day, I can afford to let in-your-face gung-ho my-way-or-the-highway attitudes take the place of actual diplomacy. At the end of the day, I can afford to let protections for the poor be stripped away and wages to remain stagnant, despite the people suffering from them now. At the end of the day, I can affort to continue to let victim blaming go on in cases of rape or excesive police brutality. At the end of the day, I can afford to allow the actual systematic dismantlement of voting rights for large amounts of the voting populace. At the end of the day, I can afford to watch as racist behavior becomes sanctioned by the head of government. It won't really affect me anyway, so at least I can sleep soundly at night knowing I didn't abandon my principles and vote for the lady who doesn't think about video games the same way I do.
The cognitive dissonance is astounding.