Hello leahjane.  Paulus is right to say that cancer is unpredictable; people may have the cancer growing inside them without knowing anything about it until some niggly little discomfort prods them to go and see a doctor.  Relationships can take many forms and I am sorry you were not able to be there with him.  My son's father died from lung cancer (he had been a smoker all his life) but did not know he was terminally ill until he had difficulty in moving his arm as the cancer had spread.   From that moment things started to move quickly.  My son's dad didn't want our son (who lives in New Zealand) to know how ill he was and tried to get me to tell him that he was was recovering well.  He really wasn't thinking straight; in these days of instant contact everyone in his family and circle were making contact and our son had booked his flight.  It may have been a similar position with your ex (the not thinking straight, that is) so don't worry yourself too much about the way things happened.  It doesn't reflect on his relationship with you.    Incidentally, to answer one question, my son's dad was never in serious pain - this can be kept under control in most cases.    Annie