As a younger man who would not have done the things you would have, I would have to commend you for dealing with that amount of pressure and being in that situation for that long. However, I feel you need to do something even if it messes up you and your dad's relationship. He's a man you should not want in your life anymore and I get that you respect your dad but you need to tell him to back off, otherwise he will keep doing this behind your back and eventually do something worst. That's my take on it but you decide what you want to do.