"bitter realization" is correct and usable in written English.
You can use it when a person realizes they are faced with a difficult truth or outcome. For example, "She had a bitter realization that she would never be able to finish her degree in time."
"Evacuation has meant for them a bitter realization of failure".
The sense of recent history repeating itself was a bitter realization for Carmichael and her family.
Acquired by Susan in 1885 after Austin and Mabel had begun their affair, the purchase is thought to reflect her bitter realization of it.
The bitter realization that 55 percent of my compatriots quite like the retrograde autocracy that Chávez represents made me want to get as far away from Venezuela as possible.
America is responsible for the abrupt end of my childhood, for my sudden consignment, at 10 or 11, to an existence filled with constant worry and fear — a bitter realization, considering that we moved from repression to freedom.
She gradually learned to live with her self-centered husband's infatuations and even with the bitter realization that he could not care less about her career as a concert pianist.
Marianne Faithfull applies her husky ruin of a voice to songs about harrowing moments and bitter realizations.
Most often, they make lists: of a lover's vows in "I'm Your Man," of bitter realizations in "Everybody Knows," of metaphorical choreography in "Dance Me to the End of Love".
This realization is bitter, it makes us anxious -- but anyone who suggests otherwise would be lying.
And within every company, there is an IT department struggling with how to make business leaders love them while pushing the bitter pills of strategic alignment, value realization, integration, standardization, self-sufficiency, and risk management.
It's a powerful realization, but also a bitter pill to swallow.
