What a difficult situation! Your family and your wife have put you in a terrible position. No one should have to choose between the people they love. As difficult as they all are, you do love your family members and your wife. Why should either be threatened by the other? Even if your parents are correct that you are not with the right partner, that is something you need to discover for yourself.
It looks to me that you have several problems all at once. You want to stay connected to your family. Your wife has significant personal problems. Your relationship with your wife isn’t what it should be. The wedding is about more than attending a family event. It is also bringing all of the issues forward at the same time.
From what you shared, it looks to me like your wife needs treatment. She may be depressed. She may have agoraphobia. Or it may be something else. It is not normal for someone to never leave her home. It is not normal for someone who has only been married for two years to be angry and abusive to someone who loves her.
Your relationship is also in trouble. There is no reason for you to tolerate being hit. It is not healthy for you to be always worried about setting off your wife’s anger. If you could fix this on your own, you would have done so already. I encourage you to insist that the two of you go for couples therapy to figure out why two people who love each other aren’t living together in a loving way.
And — I do think you need to do what you can to stay connected to the family. They have tried to apologize. They invited you to the wedding. Go. Toast the bride. Enjoy the party. Stay out of conversations about your wife. Focus on the present and let the family know that you are working on making things better with your marriage. That shows them that you want to be part of the family and that you will not choose one side over the other. If your wife objects and threatens, tell her you are very sorry she feels that way but that you love your family and you won’t be forced to choose. Express the hope that she will join you in therapy when you get back.
I wish you well.