Am I just insensitive?

My mom and I were talking during dinner and the conversation started as a hypothetical talk about a wedding (two or three years down the road.) She told me that she would like it if I had her walk down the aisle alongside me. I told her that I like more traditional things as a bride and right away, she got upset with me. So then I suggested something I thought would be a pivotal role in my wedding. My boyfriends father passed away from cancer almost a year and a half ago now and I was hoping to create something in his memory for my wedding. I asked her if she would like to carry whatever I made for him down the aisle and place that item on the chair I would have designated for him (as it is generally traditional for the father of the groom to escort the mother of the bride down the aisle). She then got even more upset and told me "I don't want to do something that is totally irrelevant to our relationship." She then said "You are being so insensitive to our relationship, especially everything I have done for you since you were a little girl. I thought I would play a larger role in your wedding. I guess I'll just go to your wedding as a regular guest." We then continued to fight and she stormed out of the house saying that if myself, my dad and my brother had never been in the picture she would have been a happier regular person. Now she's texting me going off the deep end about one little thing. She does this to me all the time. She makes me feel awful for not doing things her way because apparently I owe her something for raising me. I love my mom and she's an amazing woman but she never can take the blame or settle for something she doesn't like. It always has to be her way. I feel like she's bitter because she quit her career to raise us kids. I had a wonderful childhood and I will always be grateful for that but I feel like she expects me to repay her or do things her way because thats what she chose to do with her life. But I don't feel obligated to be that way. Am I in the wrong here? I just don't understand why she is like this.