Then we've been wasting our time. You asked for our help and you won't even take the time to read what we post.
Until you have read this entire post I am not wasting any more of my time. I was going to post the links for you but not until you have read this post. There's nothing difficult about what you want to do. The hardware is availabble off the shelf capable of doing exactly what you described.
Using a [blankety –blank] circuit, the solid-state design of this motor speed controller does not use any mechanical switches and allows the control of both speed and direction through a single potentiometer. At its center position, the motor will be forced to stop (i.e. it brakes). Turning the potentiometer clockwise will cause the motor to start spinning slowly in the positive direction, with increasing speed up to the maximum supply voltage at it’s maximum position. Turning the potentiometer in the counter-clockwise direction will cause the motor to spin in the reverse direction, again starting slowly up to a maximum negative supply voltage. Note that in it’s center position, the motor will actually brake (motor terminals will be grounded) forcing the motor to stop rather than be in a “floating” or coasting position.