No, they won't. The Republicans will move away from Trump in time to save their party. And I'm betting they will have to do so long before the 2020 election. I'm also betting that Mueller will make it crystal clear to Trump that he's not to pursue the presidency again. If it's not already happened. And Trump will declare his intentions not to run in order to allow the Republicans to save face as they leave Trump.
The way to judge if Trump has been taken under control is in observing whether he's causing anymore irreparable damage to your country. But you'll have to learn the difference between political spouting of nonsense and real damaging moves by Trump.
Do you understand what's happening with the Republicans opposing Trump on Saudi support? Don't take that as the first indication of the Republicans making the move away from Trump because it's not. It's doing nothing but allowing a discussion and debate. But it's an indication that they're ready to start making the move away from the insanity in order to save their hides.