GWU Professor Who Lied About Being Black Had Family in the Dark

A university professor who posed as a Black woman for years had her own family completely in the dark about her double life ... and now, they're utterly ashamed.

Jessica Krug -- who says she publicly identified as North African, African-American and of Caribbean descent through most of her adult life -- outed herself Thursday in a Medium post, saying she'd been living a lie ... since she isn't Black at all, just a white Jewish woman.

Krug apologized for what she described as being a "culture leech," saying she'd finally seen the error in her ways ... and that her appropriation was, in fact, anti-Black and colonial.

While it's somewhat commendable she didn't go the route of Rachel Dolezal -- who, more or less, stuck to her guns on identifying as Black -- the damage was already done. George Washington University, where she taught African and Latin American Studies, announced she won't be teaching this semester ... this after her own department tore her a new one.

Not only that, but Krug's own family came out this week and said they were utterly oblivious to the fact she'd been lying about her race. Granted, it sounds like she's estranged.

Her sister-in-law -- who spoke to CNN -- says her husband (Krug's blood brother) hadn't spoken to Jessica in 20 years ... but went on to confirm that she is certainly not Black, going on to call her "white as snow white" and establishing her Kansas City upbringing.