Maybe your father as he grew older grew less idealistic and choose to see world as it really it. Like the quote from Don Quixote ..
When life itself seems lunatic, who knows where madness lies? Perhaps to be too practical is madness. To surrender dreams — this may be madness. Too much sanity may be madness — and maddest of all: to see life as it is, and not as it should be!
Miguel de Cervantes Saavedra, Don Quixote
When cease seeing life as it should be and look up into the reflection of others, then be tainted and trapped in a body growing old and forever seeing life as it plays out.