As others have said, just because you share his DNA doesn't mean you have to share anything else with him. He is lucky to be invited to the wedding. Look in your heart. You don't need him to "give you away," as he gave you away many years ago. I have had one friend whose brother walked her down the aisle, another whose mother did, still another who had an uncle to whom she was close and had a lot of respect do it. In that case, they skipped the "who gives this woman to be his bride" part of the ceremony.

You are your own person. Count yourself fortunate that you did not inherit you biodad's lack of responsibility, or his emotional cruelty and childishness. It is YOUR wedding. The day should be a happy one for you. Decide in your heart who you would like to accompany you down the aisle, and go with it. Anyone who objects does not deserve the honor.

Sounds like you need to not expect your biological father to fill the "father figure" roll in your life. Think of him as some kinda estranged uncle, it may make it easier to deal with, and have you expect less of him.

In my humble opinion, he is lucky to have a daughter like you, and too selfish to realize it. Count your lucky stars you're not like him!!!