It's an Interesting dilemna. Here's my take,
Despite his treatment of me I could not and would not ever have abandoned my father. He couldn't help what he was. He had a serious character flaw which made him a deeply unhappy man. Bitter, angry, jealous and resentful of everyone he thought was enjoying a better life than him.
I don't wish to sound smug but I did my best for him. But I was determined not to let him shape my character or influence my life choices. I was determined to have better relationships than he did, be a better parent, be happier and more successful.
The truth is not one of us is perfect. There are no perfect parents, no perfect children, we all have flaws. It's how we overcome our weaknesses and correct those flaws that counts.
Maya Angelou said. You can forget what was said to you, you can forget what was done to you but you can never forget the way you were made to feel. I think this is probably true. But you can chose how your respond to those feelings - you can let them destroy you or you can resolve to overcome them.
Anger, bitterness, and hatred will eat you alive. You have to let it go or it will ruin any chance of happiness, serenity or contentment. These negative feelings and emotions will make you suspicious, narrow minded and will close your heart to all the good things this world has to offer.
Ernest Hemingway said "the world is still a mighty fine place". It's true, it's better than fine, it's full of beauty and magic. And it's also full of wonderful kind people who will love, cherish and support you if you let them in.
Yes there are some bad apples out there but the good far outweigh the bad.
No matter how badly you were treated bearing a grudge will get you nowhere. It will hurt you far more than it will hurt the person who wronged you. They couldn't give a toss about you so why waste your time and energy hating them, They aren't wasting their lives thinking about you so why give them headspace.
There's no need to estrange anyone. By all means set your boundaries, maintain some distance if you have to but fulfill your obligations and duties so that you can then get on with your life.
You can then change your stars and make your dreams come true with a clear conscience, safe in the knowledge that you did your best. Always do the right thing and then no one can have to cause to reproach you.
It's not about being little Miss Goody Two Shoes, it's about being comfortable in your own skin, knowing you've been the best person you can be, being able to sleep at night and having peace of mind.
There's no feeling like it.