Promised Anal No Go

Coming weeks before our wedding my wife asked me if i wanted and would do anal with her I replied yes of course I would. She told me at the time "wait till we are married you fuck my Ss all you want its yours" fast forward to today and she still won't try it with me but what is even stranger is that the other night we were talking about what would each of us really want to try. She tells me she wants to be DP cause she thinks it would be amazing??? She won't let my put my cock in her ass but she like the idea of one in her pussy and one in her asshole...i don't get it at all.