I'm going through the same thing. My dad passed away last September and one of the reasons I'm having a DW is to not have to deal with a "traditional" wedding without him here. I was going to walk by myself, but now don't want to. I thought it would be nice to ask my dad's brother to walk me, but I just found out last night that he's not coming (no reason given). I thought I'd be ok, but I got really upset when I heard that. I am definitely using a memory frame and attaching it to my bouquet. As for who's walking me down, it's still up in the air. I don't want to ask someone just to have someone, you know? I want it to be special (though nothing can be as special as your dad in my opinion). This post will probably not help you at all, just wanted to let you know that I'm having the same issue. Hopefully your mom's brother will be able to come. Let us know how it works out!