Some will sit there quietly or dozed off : Don't know how to mingle around. Antisocial.
some will vomit and get sick : Morons who doesn't know their limit.
some will become crazy or pick a fight : Fuc*ing indian. Minum like paria.

"tried many ways but so far never see her get drunk before."

Assh*le, go for sambuca, tequila, irish bomb at one go and she's f***ed.