I got married last year. My husband's father was not invited because 1) they don't talk to each other 2) he has a heavy drinking problem. My husband was very concerned that his father would show up even though he is not invited, but he didn't.

With my mother it's a different story. I had to invite her although I was afraid that we would fight. She is not a bad mean person, we just don't get along really well. Throughout the wedding she was obviously too worried (it was creeping me out a little) and she would treat me as a child, telling me to behave at the table and not speak too loud. Long story short, at the end of the day we had a fight where I said she should stop treating me like I am a small child and she told me what a horrible person I am, that my family in-law will soon find out how bad I really am and that every time she talks to me she wants to kill herself. I was shocked. I didn't want to stay in a fight with her on my wedding day so I went and apologized to her.

And that's how I remember my wedding day.

And now to answer your question... Since she is not involved in your life and her presence there will not make you happy - do not invite her and do not feel guilty about it.