Correction -- only about five years ago did Trump start donating
exclusively to Republicans. YOu have to ask yourself -- was it the price of doing business, the price of "winning" the White House, or because he really likes Republicans like Romney? Remember he endorsed McConnell in 2014. He endorsed McCain, and he endorsed Romney.
As a cost of doing business? Or because he likes McCain's and Romney's big government style of "making America great"?
You can judge what a man will do by what he says he'll do. Go ahead, you won't be the first. I am old enough now to have learned to judge what a man will do by what he does and has done.
Trump and his father donated to Reagan and Reagan had Donald to the White House and praised him.
You really should stop digging that hole you're in.