What attitudes/behaviors have you feared inheriting from your bio family at any point in your life? How did/do you combat that fear?
I've actually never feared inheriting attitudes/behaviors from my bio family. I separated emotionally from them at a pretty young age, when my dad first told me that because they fed, clothed and sheltered me I owed them obedience. After that point I stopped thinking of them as my parents and thought of them as employers (who refused to pay me or allow me any autonomy). I stopped thinking of them as moral authorities at about age 12 because I watched them behave unethically -- and against their stated moral code -- over and over, while I obeyed my own moral code. I stopped thinking of them as any source of comfort when they gave away my cat (who was my best friend), told me to stop crying every night because it was disturbing their sleep, and when I finally made a friend, told me constantly that it wouldn't last and my friend didn't really love me. By the time I was 13, I knew that I was more developed than them in both ethics and relationship skills, and I just did what they told me to do so that I didn't get hit or sulked at. I no longer had any respect for them or thought of them as people I could or should emulate. On the contrary, many of the things I learned NOT to do I learned from my parents.
1) Don't ever try to make someone depend on you as their sole or best source of love.
So even if you think that your love is so big that no one else could ever match it, you do not say this! because if you do, you are threatening that person with never being well-loved if you stop loving them. That is something that an ethical person never threatens, and also something that only an extremely arrogant person could claim. There are plenty of people who are great at loving, and if you care about someone then you want them to be well-loved even if it is not by you. It is frankly abusive to claim that you are the best love someone will ever have.
2) Don't ever reference past gifts to try to get someone to do what you want.
This ruins the gift, crushes any sense of love that went with it, and turns it into a bribe with evil intent. It's manipulative and it reveals that you have no generosity; you are merely investing in future control. Once a gift is given, you should treat it as if it didn't even come from you: that will help keep you from tying strings to it.
3) Don't ever, EVER, reference in anger a fear, insecurity, longing, or other vulnerability that someone has shared with you.
This is a profound emotional violation which not only destroys any trust they had in you, it damages part of their ability to trust other people to hold their sharing in a sacred space.
4) Don't ever destroy someone's things because you are angry at them.
This is a symbolic violence that makes it clear you only are not hitting them because you fear repercussions, not because you actually consider it unacceptable. It is an implied threat of physical violence.
5) Don't try to bond with people without considering who they are and what they want; you cannot connect with a person if you are trying to make them be what they are not.
My dad wanted me to throw a football, play basketball, or play chess, none of which I wanted to do, none of which revealed anything about me. I think he genuinely wanted to connect, but he failed utterly because he was so focused on making me share his special interest. I don't think he ever even considered trying to learn about me in order to connect. If he had, he would have quickly learned that we shared a love of trees which would have easily leant itself to connecting activities.
6) Don't approach relationships as transactions, and don't try to get more than you give.
You cannot build a relationship with someone by trying to get them to give you something. My mom wanted me to tell her "poor baby" over how my dad treated her, to commiserate and console without asking her to make any changes. When I was really young I did pat and console and unintentionally relieve the discomfort that should have built to a breaking point in that relationship. At the age of 11 I started telling her to get a divorce, that it was not fair to force the three children in the house to have to live with a tyrant. I treated her like an adult and told her "yes it's wrong, and you have to defy, say no, take action. It will not get better if you do nothing." She never listened and just stopped talking to me at all. By the time my sister was 6, my mother had started using her for comfort and no longer had any interest in me.
7) Don't call names, and if you can't resist, never EVER use a name that reinforces the insecurities the person has about their self.
My parents had names they liked to call me when they were angry or just wanted to make me feel lesser. Some didn't matter to me because they were so obviously untrue (like when they called me a spoiled brat) but other names were used to deliberately mock the aspect I was most insecure about: my body. I watched them hurt me on purpose and I decided it was wrong and I would not do that to others. I have not been perfect but since I became an adult I have called people names very rarely, and never intentionally called a name that referenced someone's insecurity, if I was aware of it or even suspected it.
8) Do not contradict what other people say is true about their self; do not set yourself as a greater authority on them than they are.
At an early age, I saw something and told my parents about it and they told me it was impossible. That broke my sense of reality and I had to fight very hard to ever trust my own senses over what someone else says is true, if there is any subjectivity to the matter. Telling people that they are not who they say they are undermines their relationship with their self, and even if you are technically correct it is unacceptable to argue with someone about it. I have sometimes taken this aspect to an unhealthy extreme and let others define our shared experiences rather than contradict them, but I think the balance lies in not contradicting others about their emotions, motives, or identity, but still being willing to contradict them about the patterns or effects of their behavior.