There is a time limit(1 year) for filing DV case. Here are the judgments you can dismiss the case for non-maintainability.
For your case she filed DV without any domestic relationship being active, so use Dhingra's judgment too.
a) SC Judgement, Judge: Dr. B.S. CHAUHAN , Date of Order: 23 August, 2011CRIMINAL APPEAL NO. 1635 of 2011 (Arising out of SLP(Crl.) No. 7787 of 2010) Inderjit Singh Grewal …Appellant Vs State of Punjab & Anr. …Respondents ; PARA 24, 25 ARE IMPORTANT & DEAL WITH OUR QUERY
Judgement: DV can't be filed after 1yr of occurrence
b)DELHI HC, Dt of Order: 29th July, 2010, Crl. Rev. P. No. 252/2010, 253/2010 & 338/2010 ; BENCH: JUSTICE SHIV NARAYAN DHINGRA ; PARTIES: Nagesh Malik vs Payal Malik
Judgement: The domestic relationship between the aggrieved person and the respondent/s must be present(i.e current) and alive at the time when complaint under Domestic Violence Act is filed and if this relationship is not alive on the date when complaint is filed, the domestic relationship cannot be said to be there.
So please take note of these judgements and fight against 498a and DV.