I'm so sorry this happened to you and that it came without warning. They can not tell for certain if a particular growth is cancer from an ultrasound, but wording like "highly suspicious for ovarian cancer" means you should prepare yourself for the likelihood that that's what it is. The main purpose of the CT scan to check whether a growth has spread and, if so, where. The CT scan cannot rule out cancer. If the growth has not spread, they still will not know exactly what the lesion seen on ultrasound is. However, if it has spread, then it is cancer.

You can handle it, whatever it is. My own emotional response may well be abnormal, but after the initial shock wore off, I have been reacting to cancer fairly similarly to any other problem. There are aggravations and frustrations, but you keep going on to the next thing. My friends and family have mostly been acting the same as before (as I prefer. I have been trying to discourage "how are you" interactions as I find them annoying.)