Is my iPhone being hacked ?

Not to sound like a nut but I have a pretty Tech savvy ✌️wife ✌️ and she is either getting all my passwords and doing weird things or just being nosy and I was wondering how?? And my situation is any time I am doing something on text or video or whatever my flashlight comes on out of nowhere and it’s not any touch nothing because I have everything turned off and I have an OtterBox case, the biggest one, the most durable one holding the bottom end of the phone and I was wondering was it because she has something on my phone software app oh whatever to do what she does best which is to spy and be nosy??

[Re-Titled by Moderator]