George Zimmerman -- Allegedly Framed By Vengeful, Lying Girlfriend

George Zimmerman was duped and done in by a lying GF who faked a pregnancy to keep him around and then framed him when she realized he was leaving her ... sources connected with Zimmerman tell TMZ.

George is now facing felony domestic violence charges after Samantha Scheibe claimed he threatened her with a gun and forced her out of their house.

Our Zimmerman sources say ... here's how it really went down:

Early this month, George made it clear to Samantha he was leaving her and leaving Florida. Samantha then dropped a bombshell-- that she was 6 weeks pregnant. George now believes she was lying about it in order to keep him in her grip.

On Monday ... things came to a head when George was packing his bags to leave and our sources say Samantha concocted the whole gun scenario as revenge.