That fateful day..

In 2009 my mother met my step father. They knew each other as kids. He lived with us for two months. It was hell, he had random moods and had a way of living I didn't agree with (leaving power on and things like that). It was also hard because he woke me up every morning and I wasn't used to that.
He often would go to his car and just sit in it, or take off out of anger towards my mum. I felt so unloved and second best by her. The first day he came to the door, he asked to see her. Not a hi or anything to me. Then told me to get his stuffed toys out of his car, Icouldn't see them and he yelled at me "IN THE BACK!"

Not long before he was going to back to his town, he asked my permission to marry her. I said yes, because I wanted her to be happy. Now, my mum and I are miserable. She doesn't care about me being miserable, but I hate seeing her sad. They have never had sex as far as I'm aware of. He doesn't care about going to get a job and treats her so disrespectfully. He just watches tv all day and mostly all night for all these years.

Now I'm living with this pain I feel from that stupid mistake. I feel so angry I said yes that day. But I feel that she would've married him anyway regardless. Part of me said yes because I knew she would've given me hell. She gave me hell years before that because of me not 'accepting' any of the guys she dated and it was all my fault. Not long ago she said "YOU WILL NEVER ACCEPT ANYONE I HAVE. RIGHT?!". I don't accept them if I feel they aren't right. All her other guys ended up being creepers or users and her current guy is one of them. I just wanted her to be happy.

I don't know what to do. Lots of people have told her to get rid of him, but she gets mad and says she doesn't want to. Yet, she says sometimes she does want to get rid of him.. then she loves him.. then she looks at a dating site.. then loves him.. she confuses me so much!!

If you were a teenager or even a young adult, I'd say that you're approval isn't really your fault. Teenagers and even young adults are far more naive and stupid than they generally think they are and this becomes more and more obvious the older and wiser you get. Your mother most likely didn't get married to this guy because you gave your approval, if that's what's causing you distress. Take it as a learning experience and learn to think for yourself instead of relying on cultural memes.

I expect they would have married with or without your blessing. You are not responsible for your mother's choices. She made her own choice. It is unfortunate that you are suffering his presence because of it, but you are not to blame for their marriage.

you're not responsible for this at all. you were just a child or teenager, and it was, in the end, your mother and stepfather's decision to get married. they probably would have gotten married anyway even if you had said no, to be honest. your parents are the ones at fault, your stepfather for not treating his family well and your mother for making a poor choice of a mate and letting him keep treating you badly without making him leave. you didn't do anything wrong, you just wanted your mother to be happy.