You are correct. The GOPe is just the Republican branch of the Uniparty. They would rather lose the House and the Senate than let Trump advance his agenda and break up the cabal that rules the country.
Of course! Because when they're in the minority, they can propose all kinds of impressive-sounding bills which they know won't go anywhere - like they did with the Obama-era legislation. Then they can go home and say "Hey, we tried!"
It's no fun when they're in charge. They have to take responsibility. Results are expected!