Me mum keeps takin' the piss out of me girlfriend, and I'm sick to the bloody back teeth of it- can ya help?

We're all from London, (England), but me girlfriend's from Greenwich, (a really nice part of South-east London), so she's really well-spoken and well-brought-up, whereas me mum's from Edmonton, (a really shitty part of North London), so she's as coarse as they bloody well come! Anyway, me mum's FOREVER makin' fun of the way my other half talks and PUTTIN' ON her gorgeous Greenwich accent, (just 'cos my girl speaks a damn sight bloody nicer than ANY of my family could ever dream of doin'- me included!), and she also looks down her nose at my missus 'cos she's got a nice few bob and me other half ain't. She had all the time in the world for me girl's parents when she thought they were shitloaded, (just 'cos they come from Greenwich), but when she found out they weren't, she was like: "Oh (!)"- (not "Oh!" as in "Beg yer pardon- my mistake!", but "Oh (!)" as in "Sod them an' all then- I ain't gonna give **** like that the time of bloody day!"- how dare she?! Who the bloody hell does she think she is?! Please help, 'cos this problem's doin' my bloody nut in, and I'm sick to the bloody back teeth of it, quite bleedin' frankly! The only reason I ain't said nothin' to me mum is 'cos I really can't be bothered with the bloody hle it'll cause again if I do say summin'! Much obliged on behalf of me and me girlfriend in advance, guys! Be lucky! :)