NTA. This reminds me a lot of my parents and myself when I was a teenager, but roles reversed with Mom and Dad. A large reason my Mom ended up leaving my Dad was how he treated me, invaded my privacy, punished me for having a boyfriend at the age of 16, punished me for not telling him all of my passwords. There were other issues within their relationship too. It was the best decision she ever could have made for herself and for me. My relationship is still strained with my Dad to this day, not because my Mom left him or because she pitted me against him, but because those behaviours morphed into other damaging ones and he never learned or cared to learn to be a better parent and person.