Is This Legal If I Use Spy Soft In My Wife Phone To Get Evidence Against Her

I want to know is this legal if I use a spy call soft In my wife phone to get evidence, I know she is cheating me for the last 7 years and also involved in some illegal activities, like satta (gambling), massage spa business (sex racket), cause 2 years before I admit a complaint against her in local thana in Delhi, but due to no evidence they didn't take any action, she has support from some local police, After that, she traps me with the same complaint that I forced her to do such l kind of illegal activities and police started to inquire about me. I got totally hopeless at that time now again, want to take some strong step against her, so please guide me, she almost ruined my social and personal life.