The Doctor is severely prejudiced against males. He rarely travels only with male ccompanions - when he is with a male companion it doesn't take long before either the male leaves or a female joins the TARDIS crew. Even the female Doctor is more enamored with female companions. So the Doctor's treatment of Jack should come as little surprise. My current issue with the Doctor is that (according to heavy debate and speculation) that Jack's attempt to warn the Doctor is what starts his inevitable transformation into the Face of Boe and it was complete waste of time and effort on Jack's part since the Doctoe paid no heed to Jack's warning. The way the Doctor acts in regards to Jack even if told that his efforts to warn cause his mutation she would simply brush it aside as unimportant.