Should I be mad at my friend for not including me in her wedding?

I have have been friends with this girl for 10 years, we met in 9th grade sign language cl. We were inseparable, often called twins, and voted the blondest duo at prom. After high school we were dorm mates at college, and when she couldn't afford the school my dad helped pay for her knowing how much she meant to me. We only went to that school freshman year, but got homesick and went back to our home city. We attended another school together and kinda drifted apart due to boyfriends. I admit to not being persistent in hanging out with her for the last two years but when we do hang out its like old times. She recently got engaged, I introduced her to her fiance when we were 16, and she left me out of her wedding party. I don't think it would hurt as much but she included my cousin as a maid of honor, who she has only known for a few years because they worked together. The other bridesmaids she has known for about 1 year. I know I shouldn't be so upset but I feel like we have such a past together and am really hurt that she completely left me out. We have talked about it and she said that she didn't forget about me but was worried about symmetry an needed another groomsman to add me. Now Im afraid she will ask me to be included out of pity, and I'm too embarred to accept if she does. Do I have a right to be so upset and hurt or am I just too sensitive. I'm so confused and have cried about it because I don't know if I can even attend her wedding now, or even remain friends with her. She also told me that she picked her wedding party based on who she currently hangs out with. In my mind I believe that doesn't matter, it should be people that have meant something in your life. I don' know, very upset.