1. You know facts better than what have been put here in your brief on ‘adultery’ allegations. This is said least it backfires upon you and she gets divorce on ‘mental cruelties’ ground and thus gets share of alimony forever.
2. Having hinted what I felt is right when dealing with such briefs I would rather prefer you to hire a seasoned advocate whom one can found via reference or searching for one from large database of Lawyers in LCI Lawyers Search box above. The case of these natures goes for 1 to 2 years as allegations are very limited nature and only attributes it carries is ‘following’ or ‘not following’ when Court is directing parties for DNA testing on an application by claimant.
3. You may file a criminal complaint against her b/f in a criminal law dealing Court and a civil matter under civil family Court by way of a petition leveling allegations of ‘adultery’ of spouse making her b/f also a party thus praying for dissolve parties marriage along with a misl . Application request for voluntarily submitting samples not only of parties minor child but spouses as well as her b/f to DNA paternity group testing with your samples. Request in same misl. Application direction for double blind coding system while testing DNA samples of parties at a Govt. FSL where ‘there are a large number of samples and more than one Investigator is there’. This is a safety clause your side should prepare early with. It is obvious she may ‘refuse giving consent‘ citing counter allegations upon your mentality and so will third party her b/f and her side will quote ‘conducting DNA testing on minor child makes society shun the minor or treat the child as illegitimate’ emotional lime - soda counters, well in such cases, your side counter arguments should be based on Apex Court decision in ref.: Gautam Kundu Vs. State of West Bengal & Anr. [(1993) 3 SCC 418] where the Supreme Court while dealing with a question of disputed paternity, held that blood grouping test is a useful test to determine the question on disputed paternity. It can be relied upon by the Courts as circumstantial evidence, which ultimately excludes certain individuals as the father of the child.
4. Also if for some lack of pleadings if DNA testing is not allowed under affidavit submit independent test results that you have obtained as ‘earlier’ not giving consent by wife and her b/f means onus of allegations shifts upon you and the more stronger this onus is dispensed with in affirmative the case now shifts in your favour and divorce on grounds of ‘adultery’ is granted in your favour.
5. An adulterous wife is not entailed for any ‘alimony’ so your notion on paying her alimony is being laid to rest in peace. Now, since the divorced parties child cannot be treated as ‘illegitimate’ so you have to give maintenance for the child which can be debated on co-extensive proportion if wife also shown to be earning.
6. As a legally wedded husband you have every right to carry out such DNA test without consent of mother of the child as later the same society will blame you of lack of delinquency being her legitimate husband.
7. In above reply I have stated how to claim divorce on adultery grounds without meeting alimony yet giving proportionate maintenance for parties minor child under assuming parties married under Hindu Marriage Act. While claiming divorce if you want you can claim minor child custody as Apex Court has already said that an adulterous wife cannot be entrusted with custody of minor child.