Very high cholesterol is a concern, as you are well aware, for many reasons, including the potential for complication involving the blood vessels. Aortic aneurysms are common in older people, but they are also more common in those with a family history of having them. For that reason, you are at increased risk because of your father's history. Smoking is most definitely related, in that smoking likely increases the incidence of aortic aneurysms (and a myriad of other health problems), but it is not clear whether or not high cholesterol is involved to the same degree.
Most aneurysms will have some atherosclerosis (hardening of the arteries, with high cholesterol being implicated in the formation of the same), but it is not clear if the hardened artery dilates or if the dilated artery hardens. One study found a group of people with aneurysms but without atherosclerosis, and so the relationship between high cholesterol and aneurysms is somewhat murky. That being said, the appropriate medical management of your high cholesterol and blood pressure are vital to your overall well being, as they will cause many more problems other than just the potential risk to your aorta. Please work closely with your primary care doctor
to optimize your health and prevent long term complications.