The ascending is much more difficult than a descending aortic aneruysm. My Dad had an ascending and was told that at the present time it wasn't possible to do that type of surgery.
My mom had a repair of a descending thorasic aortic anuryseum a few years ago - she is 76. She also had an open repair of an abdominal aortic anurysem last year. Unless there is another reason that you are unable to have surgery, age is not necessarily a barrier. My mom had her surgeries both done at the Cleveland Clinic. The vascular surgeons there do many endovascular repairs (that was what she had for the descending repair). It is not a simple thing but with the right doctors you can have a great outcome. My mom is doing great!
I don't know where you live but I would strongly suggest you go to a vascular surgeon who is affiliated with one of the larger hospitals in your area before you give up on the idea of surgery. There is a procedure that is called an endovascular aneurysm repair. They put stents in the aorta to seal off the aneurysm via 2 incisions in your groin. This procedure came about because so many people are not ideal candidates for the open surgery for whatever reason. It is routinely performed on people up into their 80s. Do not accept the "no surgery" soley because of your age. Good luck.
Your Doctor might consider an anxiety medication to help you if you ask. I read somewhere that a stent type product is available for your condition. I believe it was available for ascending which in the past was not availabe. Press on with a medical university to help you out.