Lil Scrappy and his mother, Momma Dee aren’t  taking kindly to accusations made by his ex-GF … Scrappy tells TMZ Diamond is a “lying industry ho” who’s as fake as her phony  teeth and butt.

Diamond gave a radio interview Friday blasting Scrappy —  accusing him of physically abusing her — and claiming Momma Dee stole her Louis  Vuitton purses and ruined her credit by trashing a condo Diamond helped her  buy.

Scrap tells TMZ Diamond lies like a rug … saying he was never  abusive and never once put his hands on her. Scrappy says she’s trying to make  herself relevant by throwing shade … even though he gave her a start in music  and bought “her $20K teeth and her fake ass.”

He says Diamond’s story of  Gucci Mane slapping him down in a club is all BS. Scrappy insists they had a  shoving match, nothing more.

And Momma Dee tells TMZ she never got  anything of value from Diamond because “Diamond ain’t never had s***.”

Momma says Diamond’s a “lying chamber maid” who’s mad because she’s not  banging the prince anymore … and says Diamond will never have any money unless  she gets a “douche deal for her stank-ass p****.”

BTW … sources close  to Diamond says her ass is real and she paid for her own damn teeth.