Sandra, I had part of my tongue removed in 1987 (at the age of 32)and a neck dissection on the right and then in 2001 had more of my tongue removed and a neck dissection on the left. I didn't require any bones in my jaw or face removed as some others have. I was very paranoid about my looks after the first surgery. I was in grad school and went back to class less than a week after surgery. It was obvious that I'd had major surgery and people did stare at me, however after I started to heal no one seemed to notice much or even if they did they kept their stares and opinions to themselves. For a while I wore scarves and turtle necks and then decided it was more trouble than it was worth so I stopped. Now I have scars going from each ear, down my neck, they meet above my throat and continue up to my chin. To be honest, I've gotten used to it and I don't feel at all uncomfortable meeting people for the first time anymore. She will probably be more bothered about her change in appearance than will others initially. I now wear scoop neck blouses and started wearing necklaces again (I didn't for a while because I thought it drew attention to my neck). I also have some skin discoloration from the radiation.
I am more paranoid about my voice, which is still understandable but slurred and raspy. I feel that I have to explain when I first meet people that I have some difficulty speaking. What speaking, eating, drinking will be like for your mother is hard to say. It will depend on the surgery and how she reacts if she has radiation. I can now eat soft bland foods and drinking is ok. I wasn't able to eat for several months and had to have a feeding tube as did many others who have had oral cancer treatment.
What I can say without reservation is that there are people who can help her in these areas. Speech therapists can help with the swallowing and speech and it is better to start earlier rather than later. Make sure that the person you are dealing with has experience in dealing with oral cancer patients and really understands the issues. Physical therapy can also help if she has neck surgery.
As you know, your mother has a tough road ahead but the support of people who care about her will be of tremendous value to her. Please feel free to contact me if you want to talk further. Also please keep posting on OCF. This is an incredible support group and everyone will want to know how your mother is doing. Tell her that there are many people out in cyberspace who are pulling for her!