Where did I go wrong?

My oldest son is 9 years old. He used to come and talk to me all the time. Then suddenly he wasn't able to talk to me about things. Now he comes and stands in front of me and just stares at me. If I ask him what he wants he puts his head down and talks so softly I can't hear him. If I ask him to repeat what he said he starts to cry. Sometimes he will write out his question, toss it at me and run away. The thing is I usually say yes.

This has been going on for a couple of years now. It is getting to the point where I just want to send him away as soon as he comes to me with that look on his face. I don't even want to try to deal with him because I know it would be easier to milk a bull that to get any information out of the child.

I know something has to change, but at this point I don't even know how to go about getting there. At the moment I am getting frustrated with him and yelling at him. I know that doesn't help the problem, but asking him nicely doesn't get through to him either. At this point I just want to scream.

I always hoped that I would have a really good relationship with my kids. I wanted to be the mom that all the kids came to. I want to be the cool mom. I feel like I am the mom that just yells at my kids and can't get them to listen or get through to them. I wanted to do 'do today' with my kids. My dad used to sit with us before bed and ask us 'what did you do today.' It was shortened to do today. I want that. I would ask my son when he got home from kindergarten what did you do today. NOTHING. I know you did something, what was it? Ever since then I can't get through to him. What happened? Where did I go wrong? At what point did I lose that little boy that use to tell me everything? I don't know. I do know I need to do something about it. I jsut don't know what.