Check out what the Republicans are actually up to and you'll see what I mean.
It's hard for people in other countries. The Tories would be centrist here, our Democrats would be center-right in the UK.
Notice the scenes from the Republican National Convention with the flags and Christian crosses splashed everywhere. Read up on what happens to GOP politicians who deviate even a fraction from orthodoxy.
I know there are Republican citizens who aren't right-wing maniacs, but the maniacs have seized control of the party. I can hang with Republicans if we avoid politics. But the thought my wife was voting for a party with the GOP's track record? That's a hard no.