Well, normals will always push the opponent back; they literally can’t keep approaching safely and you’ll get an opportunity to fight back. If it seems as though they keep on approaching with them, then maybe you need to recognize when some of their normals are negative on block so you can fight back with your own normals.
Also, although Ryu has stubby normals, a hadouken just out of range of all his other normals is a good tool in itself. It’s hard to react to it when it’s still somewhat close to the opponent. Just don’t get carried away with it.