Can I father relinquish his right to a child in the state of Indiana with out the mothers consent or the responsbility to pay child support in the future?

Nope. Probably can't even with her consent except to clear the way for an adoption.

It is for an adoption...

Then why doesn't he have the mother's consent? I'd assume that SHE would want the adoption to go through.

She is a very difficult individual. She is the one that wants this but knows that once this happens there is no more contact with the father. It is a very bad situation. The child is in no danger physcially but emotionally he is a wreck because these two hate each other so much.

So the whole story is that she is re-married and the step-father is going to adopt, but the biological mother doesn't want it?

Honestly I don't know whether she wants it or not. She feeds on drama. I think with out her sons father in her life she would have nothing to talk or about. I am the 'mediator' in the situation but it is very hard to side with her when I hear and see the things she does. I could never imagine a father giving up on they're child until I was brought into this all of this. I live with him but I am friends with her. I don't know whether I am coming or going. I know it is very hard to understand but the stress is becoming unbearable.

Basically it goes like this:

Most states require that you be married, and married at least a year before a step-parent adoption can go through.

Most states will also NEVER terminate parental rights except to clear the way for an adoption, or if the parent is a danger to the child.

Ending parental rights does NOT end child support--parental rights and parental obligations are two different things.