Technically, it's in the republicans best interest to get rid of him because... Pence is next in line. And arguably, he is worse because he actually has an idea of politics
It's in their best interest for the long-term survival of their party, but Trump still enjoys wide support among the Republican base and holy hell will reign down upon them if they oust him without the base shifting first. Not only that, but having the first impeached president come from their party would be...significant. He will not go quiet into that good night; he will try to drag everyone in his orbit (at this point, practically the entire GOP apparatus) down into the void with him.
It's clear that their hope is to stick by him through the 2018 midterms in a bid to keep Congress, then let the chips fall where they may (at worst, distancing themselves from him and running a different candidate in 2020.) He's so far been a disaster for getting legislation through, but he did get them Gorsuch on the bench and there's a very real possibility he could appoint 1-2 more justices in his first term. This is the golden goose for the GOP: the judicial branch has been the only effective tool against Trump so far, and they froth at the mouth when thinking about swinging it conservative. They've already gerrymandered and indoctrinated rural America through talk radio and Fox News to the point that they will maintain an edge in congress for a long time to come; the left has a huge swatch of fickle idealists who abstain/"vote with their conscience" and allow conservatives to take the executive branch on an 8-year cycle; taking over the last leg of government has now become the true goal.