"Was this before or after God rejected King Saul and and God sent Samuel to anoint David, King of Israel?"
This sidesteps the issue: that David capriciously stole wives from his countrymen, conspired to have them killed in combat, and was an all-around reprehensible cad for most of his life. You can't ignore this. Well, strike that. You can, I guess...
A "divine" mandate centering around a possibly fictional or at least embellished character from Hebrew lore says more about the deity doing the blessing than the man abusing his "divine" mission.
"Only Christophobes and homos give any credence to this falsehood."
Art. David said very, very clearly that Jonathan's love was better than the love of a woman. This DOES NOT mean their relationship was necessarily sexual (it is possible to actually love another man and never, you know, go there). However...
the word ahba, Strong's # 160, can mean "familial" love or the "romantic" variety. The same word to describe how Ammon felt about his sister Tamar before he raped her. So, sorry. The love of David's life was Jonathan (he never speaks of his many wives in these terms, by the way), and the nature of their relationship is slightly cryptic. I don't think it was necessarily sexual; who knows. It doesn't matter. David loved the guy and there is nothing you can say to dispute that fact. (Well, strike that; you're a glutton for punishment, Art, so knock yourself out.)
"I'm sure David insisted that his son ravage his daughter..."
I never said he did. But he did keep his peace and do nothing whatsoever to punish or reprimand Amnon, either. Thanks dad! Think about it, Art. A son of yours rapes his sister, what the world would YOU do? A who-knows-till-you've-been-through-it BS excuse won't cut it, either. David knew the law of Moses. He did nothing whatsoever to bring Amnon to justice. Instead he waited till Absalom murdered the guy and staged a palace coup. The man after God's own heart fouled this up. Period.
As for Shimei: David promised him his life would be spared (1 Kings 2:8). On his death bed, the man after God's own heart utters these last words: "His hoar head bring thou down to the grave with blood" (v. 9). This bloodthirsty philandering butcher has one last thought before passing into the great beyond: son, kill that guy who insulted me many years ago.
Sounds like a mobster or thug, to me.