It is really difficult to see a loved one suffer under any disease, it is very hard that we're not be able to do "anything" for them, so I understand you perfectly, I consider that the most important thing is to accompany them to the end and give them a lot of love, to be feel genuinely loved and supported in the end, whatever your father and mine have finished, they should be in a better place enjoying their well deserved rest. Thanks for read it :)