You can't prove a negative. What evidence would convince you that no god exists?
This is kind of the point, really. Scientific concepts have to be falsifiable - for example, if a form of life was discovered that was fundamentally different to every other in its construction, that would potentially disprove evolution. By contrast, religious concepts are not falsifiable: you can never prove that a god does not exist, because a being with the powers of a god could always carefully arrange the evidence to hide its existence.
You are absolutely correct in what you are saying, as I work in a laboratory and read the history of science, both chemistry based and biology based. The problem I am having is that up to the age of 8-9 I attended a church Sunday school, which thought me the better sides of Christianity, such as helping others, and being tolerant. That's why I feel torn and dare I say it, confused. I know that people don't need religion to be tolerant and helpful, but on the flipside, some people might require it to be tolerant and helpful.
Like you said fraggle, you can't prove a negative, and absalute proof, to me anyways, would be God himself manifesting himself/herself/itself and appearing on earth. And doing the impossible feats, in a controlled environment, to remove any possibility of a fluke etc. Such as a medically checked blind man since birth gets healed, abd sees, all under the scrutiny of scientists. That way, all sides could be contented.
I'm not sure if that last wall of text made sense, but I hope that it did.