There is no linkage between the 498A case filed by you and the divorce case. 498A cannot be taken back as this is non compoundable offence it is not he who has to linger on he has to defend this case as after the FIR is filed its not you but the state Vs your husband you will just appear as a witness as it was you who filed the case. This case once filed cannot be taken back by you even if you want to.....though this can be quashed by HC if there is some compromise.
Divorce is a different issue altogether there are two things : 1) he may feel threatened and agree to compromise with you and would give you divorce and alimony to save himself his family from such legal cases.
2) He may try to fight back and take revenge from you for the days he spent in custody and the loss of reputation. if he opts the second thing then you wont get divorce easily and even if you get it from the lower court he may challenge the same in HC and then SC.
A prudent person who decides to take revenge will not let divorce happen unless the 498A is pending as he cant spend his life fighting the State even after divorce and the wife leading a happy life.
So lawyers do advise one side of the story which results in filing 498A cases and results in suffereings of both sides and leave no chances of reconciliation.
The FIR case you dont need to fight its the state fighting for you...you are just a witness so concentrate only on the divorce case. May be your lawyer would have suggested so that fast track court can help but the other side would have a lawyer too who will advise the counter to stop you from getting the same.
There is no easy way out depends on how much impact the custody have on your husband and his family if they are frightened and want to come out of this than you will succeed and get divorce easily but if he is the other type (that you should know) then there is no easy way out.