I obviously have never met him, going off of actions only. How he has treated his ex-wives (while married to them), how he has treated his ex-cabinet, ex-business associates, his ex-workers, etc. If a handful of people said that he was a jerk, likely a political hit. When half of his own ex-cabinet is calling him out, you know “the best and brightest” that he hand chose, maybe there is a little truth to it?
He shows narcissistic traits. Usually anyone with those traits will be “a really nice guy” to those that serve their interests. To anyone else, they mean nothing to him. Not someone I’d consider to ever have the best interests of a country, especially if those interests would be different than his own. Those actions have been hard to ignore, by me at least. Some others either choose to ignore them, deny reality, or drown out any other media that doesn’t praise his every move. And yes, I know it happens on the other side as well. Not sure if ever to the extent as Trump though.