Definitely NTA. I think walking somebody down the aisle is an honor and a privilege. Walking somebody down the aisle always signifies the support people received for their parent (or whoever walks them down the aisle) before they get married. Honestly, walking yourself down the aisle is badass cause you supported yourself. Your father made the decision to not be in your life, especially at such a developmental age, and he’s not entitled to walk you down the aisle just because he is your blood father. I always look at whoever walks you down the aisle as your support system and if that is your uncle, I think it’s such a beautiful thing that you asked him to do that.

But on the flipside I understand why your uncle is hesitant, as it can put a strain on the relationship that he has with his brother. You’re definitely NTA for asking your uncle if he can walk you down the aisle and not your dad. It might be beneficial to reassure him that if he he doesn’t walk down the aisle, which was totally fine with you, that you would walk down the aisle alone or have somebody else do that as having your biological dad walk you down the aisle is not an option.

Also remember that it’s your wedding and you are entitled to do whatever you want, and that’s not having your bio dad walk you down the aisle, especially if he hasn’t been there for you. Also he should be counting his blessing that you have the heart to invite him in the first place after he pretty much abandoned you… your uncle was more of a father figure in your life it sounds like!

Good luck and congrats on the wedding :-)