Why? Again?

Why? Why does what was beautiful suddenly shatter in hindsight because it concealed dark truths? Why does the memory of happy marriage turn to gall when our partner is revealed to have had a lover all those years? Sometimes the memory of happiness cannot stay true because it ended unhappily. Because happiness is only real if it lasts forever?

This is almost true for all relationships isnt it? So happy together for so many months then when it all ends, the two parties revert to strangers. It is as if everything that was shared has never been shared. Hahaha. The way humans/homosapiens behave..... Tragic indeed..