You're not just voting for President, you're voting for the rule of law. You’re voting for who replaces RBG on the Supreme Court. You're voting for federal judges.
Your 1st & 2nd choices may have dropped out. Your 3rd might too. But no matter who the nominee is, they won't be perfect. They won't pass your purity test. But every single one of them will be better than four more years of Trump!