The rest of the talk seems like bullshit, and I'm sure they were pretty condescending, but I think their concern for their daughter was legit. I've known a couple people with MS (and a good friend who looks like she might have it). It takes everything from you. It can go at a pretty fast clip (depending on the person), and the further along it is, the more you have to rely on other people. At some point, you literally cannot take care of yourself. If I were her parents, I would be scared to death for her, because at some point, she will need someone to take care of her, and if I couldn't do it? I think a lot of people with MS end up relying on either their parents, spouse, or grown kids to help care for them. And if she wants to get remarried, that will be a huge challenge, because marrying someone with MS means you'll probably watch them die of MS, and you'll end up taking care of them for years beforehand. Is it worth it? I think people who marry into that probably would think so, but it's a very difficult life.
Also, and I'm not sure if this came across in my post, but the MS came up once in her talk. The fact that they were sure she wouldn't find a husband because of her lower status as a divorced woman with a child came up over and over, and that was the context for "who would ever want her?"