While my wedding wasn’t what you’ve described, my father and his family (my parents are divorced), including one set of grandparents didn’t attend, my husband’s best man pulled the “didn’t ask for time off” card, and one of my bridesmaids emailed me to say she couldn’t come after I paid for her dress (which she never repaid me for). On top of that, my aunt had a fight with my grandmother (on my mom’s side) and decided they wouldn’t be attending, either, which left me without a ring bearer at the last minute, and short one reader.
But when it came down to it, it was still the happiest day of my life. We were married by the priest that was involved in my RCIA program, and we were very close with him. And once the Mass started, all I could see was my husband, the priest, and the life we were starting together. (Getting a little weepy here…yay for pregnancy hormones! ;)) By the time the reception was over, nothing mattered except getting to cuddle with my husband for the first time and looking forward to what the Lord had/has planned for our life together.
No matter what happens, your fiance and the Lord are with you.