I am sorry DS.
My father and I don't have a good relationship, (this due really to him) but I could never imagine him not having had a part of my wedding no matter what. He didn't walk me down the aisle though, but still, I don't see why your daughter doesn't put her foot down and refuse letting her mother say no to you.
Have you talked to your daughter first hand and (without letting her know other people have told you) seen what she had to say about her wedding? I think if possible, you should do that. At very least, she should be the one to tell you whether she wants you there or not, not have everyone else do it (maybe even for her).
This is tough, but I wish you all the best. I hope that your daughter one day wakes up and realizes what her mother and uncle are doing. Your parent's shouldn't be left out either.
This is so sad.
I will keep you all in my thoughts and prayers. I hope that maybe something can be worked out so that you can attend. My thoughts to you hun.
~Amanda