I am so sorry to hear about your tumor.
I had a couple of pituitary tumors myself - and when I found out, well, it was very scary and I think everyone freaks out about the potential changes. Part of it is oddly muscle issues and one effect is my eye muscles and I have no depth perception due to my eye muscles.
I have had a friend that had a very aggressive acoustic neuroma and he lost his hearing and had a facial palsy. I have had family members with Bell's palsy (where half the face is paralyzed).
It is natural to worry about scarring, what you will look like, feel like and how you will manage. After all, it is all unknown at this time. I would hope that your partner would not mind seeing a surgical site - think of it this way - if the shoe was on the other foot, your focus is really concern about the other person, not exactly what the person or the site looks like (and if they are that concerned, perhaps that is not a correct focus?).
Until you have the surgery, you are not going to know - but you can check out the laws to see if you need to have two functioning eyes to drive. You may have restrictions such as only day time driving.
The deafness can be resolved by the use of a cochlear implant. Plastic surgery can help with some palsy issues. You may need eye drops to help if it effects an eye lid.
Stairs and all is all a depth perception issue - if you have only the use of one eye, then you may have issues until you adjust. I pretty much learned to cope. Physical therapy can help with balance issues. It is going to take time - it is going to be a change and there will be an adjustment period to get back to the new normal.
Whether you can work or not will depend on the tumor and the skill of your surgeon.
If you are this upset, you may want to get counseling beforehand?