Unfortunately, anon, there’s not an easy answer here. People’s words effect us, and how we feel, even if the person saying those words is a stranger. When the person is a parent, someone who is supposed to nurture us and be trustworthy, then it is even harder not to be effected by those words.
My father is also very verbally abusive, to the point where I sometimes ‘hear’ his voice in my head when I do something that would have made him insult me, were he around to see it. Part of me has internalized that damage, and I am still recovering from it
One solution to stop feeling the effect of your father’s verbal abuse would be to cut contact with him. He can’t insult abuse you if you don’t provide him your presence or attention. After that you can start to process and recover from the damage that his abuse has done to you. I understand that that may not be possible or feasible for you to break away from this relationship right now, however.
If you do have to spend time with your father/communicate with him, here’s what I recommend.
Try Always have a ‘chaperone’ or emotional bodyguard with you when you talk to your dad. This is a person you trust, who you know will be able to separate what your dad says about you from reality, and can assure you that what your dad is saying is bullshit.
If you can’t have an emotional bodyguard with you, you’re going to have to be your own emotional bodyguard. Remind yourself that you do have worth, and what your dad says comes from abuse, not from reality. Always when you interact with him, do something good for yourself after. Take a relaxing bath. Make a meal you enjoy, do something healing.
Another great tactic is to write down the things that your abuser says and keep them somewhere. That way you can either publish them via the net and other people can assure you they aren’t true, or you can look over them again when you are more clear headed and remind yourself that what you are looking at is abuse, not reality.