Can i fall in cyber law?

U can file a complaint and let the fact be brought out by the investigating officer.

Yes you have committed crime under law you can just keep the records with you and state during trial that you have knowleged of such hidden facts about your wife and can ask court to investigate the same accordingly but one false move will entrap you so its recommended to discuss the case with your lawyer and move forward in this case in no circumstances you should disclose how you got knowledged of her acts , but just you are suspicious of your wife activity and need court to trace and interven the same

I could understand everyone. I have a five years old son staying with her. I thought this 497 case will help me in my child custody case. What should I do?

If you have clinching evidence to prove her adultery, proceed with it and bring her to book.  Let she go for a complaint against you for the offences of hacking her fb account, let she prove it, but she has got to repudiate your claim about her adultery, so will she go ahead with a complaint under cyber crime law against you?, in fact your complaint may help you to retain your kid with you in child custody case against her.

Thank you Mr T Kalaiselvan

you dont have to say whole stuff brother just made up a good story say she forgot to sign out ...... i opened the browser and her msgs popped in front for me .... all the best 

There are certain decisions that in case of 498A if e-mail account is hacked and it is established that it was for genuine purpose,the act is not punishable.