I agree with Rock, round pen work will help you feel more connected to your horse, thus regain the confidence of being a leader.
Also, make sure that you strengthen your back and abdominals (yeah!!!) by doing other things like walking or dancing or yoga a LOT before even getting in the saddle at all.
Walk with your horse on the lead, and stand as if you ARE in the saddle, knees bent back erect, core muscles ON and hands in front holding the reins. Ride your horse through a test (your legs are your horse, ok?) just on your own feet.
Roll around on the ground to reassure yourself you are not made of glass.
Get really happy and excited for each short ride you take as you push the edge back out to where it used to be.
Best of luck!