I have a 20 year old Arabian horse horse abought 8 months ago and i am scared to ride him!?

ok so I love horses always have i am 56 sad to say, but decided this is it I am getting a horse. rode when I was a teenager just an old welch pony nicest, best pony ever. So i went with an older horse, not the prettiest old guy, but I fell in love with him. he was very underweight when I got him nursed him back and he looks fantastic. Tried to ride last summer, no bucking, no rearing. just jigging or dancing as I call it when he got to a certain area in the arena, scared the poo out of me. and ofcourse he knew it, my friend said i turned white as a ghost. so after a few times of that and him figureing out I am sure that is rider was not confident I said ok its lesson time. took about eight lesstons, and decided done, for now its winter up here comeing so I will spend my time bonding. leading working on ground manners and just generally trying to gain his trust. I have bought all new tack to insure all is going to be comfortable and fitting properly for him, I have read about eight books this winter, watched countless dvd's on riding and have a friend at the barn who has helped me tremendously, I have learned patience, and kindness throu all this. hopefully I have always been kind. It has been a wonderful experience and I feel I have learned so much, and I feel the trust we share. Sooooo I am still very nervous to ride!! anybody else ever experienced this so do I just take a deep breath relax and go for it? I think its my age! i want to do this so bad but I don't want to die doing it LOL. I feel like he is gonna test me, but I have to have the courage to know it is a test and I can ride thru it. :(