For a long time, I essentially thought the confusion of the terms was because they were effectively synonyms but people wanted to get away from "morality" because they merely wanted to feel like their ideas were unconventional, like their belief that murder is wrong is founded in something fundamentally different from any variation of a religious belief that it's wrong because life is valuable, or a utilitarian belief that it's usually wrong because it causes more subjective harm than subjective good. A way to talk about right and wrong while simultaneously being arrogantly dismissive of whatever they associate with conventional morality, or just religion.
In recent years, I'm seeing definitions like "Morality is understanding the distinction between right and wrong and living according to that understanding, and ethics is the philosophy of how that morality guides individual and group behavior. The two are closely related, with morality being the foundation of ethics," and then turning around in another place and finding the exact same definition, only reversed.
So now I get to stop being pessimistic and start being blissfully confused, a rare transition and a happy side effect of growing out of self-assured cynicism.