1.You should not have succumbed to in-laws blackmailing.
2. Having succumbed today you have no available grounds to dissolve the second marriage. All that you are justifying is bald in eyes of law.
3. First go and get complete file ‘certified copy’ of ‘withdrawal (quashing)’ of previous case that happened in facts of first wife suicide and follow-up criminal charges upon you by in-laws.
4. Now you have to create grounds; write every week a registered letter to wife to re-join you at your place of current living and mention in the letter that both of you got married on date/month/year (2.5 years back) and you (wife) has not consummated marriage nor living with you and you love her and cannot bear the separation before eyes of society that you keep at this place wherever you are saying to me you are currently living alone. Write same lines every time for next six month. Once six month passes of such letters being sent each month to her, appoint (meanwhile) an local advocate and file case of divorce under 'desertion' ground citing 2.5 years old marriage and neither consummated nor wife inspite of repeated requests by way of letters has joined your company and also mention chronologically in the start paras of the suit matter that some 6 years back you married some Ms. X and she committed suicide and in-laws implicated you / family members into criminal cases and it was compromised on assurance that I should get married to then my sister-in-law who is respondent wife herein. Once parties reached compromise the earlier criminal complains were quashed and the parties did Court marriage at such and such Court / place / city. Soon after I requested my wife to consummate the marriage and she asked time and meanwhile I returned back to my place of duty in such and such city and since then living at this Court jurisdiction. From time to time I approached my wife to consummate and or live with me and annexures (copies of letters) are annexed for perusal of this Court. My wife since last 2.5 years has neither consummated our marriage nor ever once lived in company of her husband and thus has 'deserted' the company of husband / marriage.
5. Once you create above grounds and file a divorce case on more or less above facts the reaction of in-laws would be to file again a case of dowry etc. upon you / family and they will again level allegations of your previous marriage and suicide of their first daughter in cruel hands of you but will not mention the ‘withdrawal nor their second daughter marriage into their rejoinder allegations paras’ to your divorce case. You may be arrested or you may apply for Bail as per State provisions since this time in-laws are not going to sit tight when they receive divorce notice.
6. Here for bail / quashing use certified copy of earlier case withdrawal / quashing to quash repeated charges of dowry etc. upon you and co-relate para 4 emotional blackmail facts paras of in-laws while seeking bail / quashing.
7. This time if you are lucky then inspite of both parties guilty of conscience one party will definitely bail out of the self created mess which comes out from your brief. Now that depends upon ability of a skillful advocate either party hires.
8. At the end I will once again say you have a hopeless case and should not have succumbed to in-laws blackmailing in past. Nevertheless I donot know the truth (facts) like under what circumstances first wife committed suicide and why the criminal case should have been allowed to have withdrawn, but if you understands the above logics (strategy) para 4 probably you may come out second time lucky. And once out of the mess donot ever get remarried is the only lifetime caution I can tell you TODAY otherwise third time you will never come out of such legal mess believe me.
OR
If you cannot do all / some of the above then sit tight and carry forward in life. Marriage is not everything. Reason being if you can succumbed to in-laws blackmailing and to quash criminal cases you marry SIL and not even consummate or order her to live with you for 2.5 years more after first wife suicide then it is better not to stir the nest.