I would just say that I appreciate his talent regardless of his political opinions or his personal life and hopefully someday he will be able to do the same. Then have every picture possible taken by his painting.
I understand what you are saying. Generally one buys art because it speaks to them. The buyer appreciates what the artist did or the feeling that are emoted when viewing it. But I personally could not look at the art as I had before the artist made a point of publicly insulting me, my father, and all who voted for my father. I could no longer enjoy looking at it. I would not want my children growing up and looking at it, knowing that the artist hated their mother and grandfather.