I know that some stepfathers are not so bad, but my has always ignored me.
I'm so sorry to hear that. I actually have had 2 step fathers, that were married to my mom, one supported me financially growing up and the other is current and is more involved emotionally/mentally then the other was.
You are lucky. My stepfather loves my mom very much, but I am not so important to him. 
Well you should be because Im sure you are important to her and thus you should be important to him. You know there is an opera thats like cinderella but with a step father instead of a step mother, I thought that was interesting.