-Don't donate any more money to anti-gay laws.
Or not. In which case I'm prepared to change my views. But I'm not prepared to change my view about the 14th Amendment and the wisdom and decency of assuring basic legal equality for everyone. To my mind, that is an entirely settled issue. I'd no more go back on that than I'd tolerate a return to slavery (which, let's not forget, is the horrible error that necessitated the 14th in the first place).
But in any case, Thiel gives money not only to candidates of the Libertarian Party, but also (in fact, mainly) to the regular, anti-gay GOP. It could be that he hates gays. It could be that he doesn't, but just considers funding anti-gay propaganda to be acceptable collateral damage in a quest to promote the Republican Party's other positions. Either way, he's a much bigger problem in my mind than some small fry giving 4-figure amounts to them, because he's giving 6-figure amounts to the bigots, which they can use to promote bigotry.
For any flourishing society, a broad spectrum of opinion is vital. But when you start attacking the underlying system that make that open society possible in the first place, you've crossed a bright and shining line.
After all, not everything is up for debate. Indeed, that's the whole point of having constitutionally protected rights. People are comfortable with the back and forth of democratic rule if - and only if - they know that their fundamental human rights and basic legal equality are beyond the reach of public debate.
Put that in play, and all bets are off.