Perhaps you and your son can agree on a number of visits a year that he is able to make. Asking for that kind of commitment from him would not be unreasonable given the situation you find yourself in. As well, normally air travel will allow us to fly almost anywhere within a 24 period, barring additional Covid disruptions so he shouldn’t have to take too much time out of his agenda. I spent 40 years living in Ontario and working primarily in English. My husband who is a francophone wanted us to move back to Quebec where everything happens in French. Fortunately we are both bilingual so language wasn’t an issue. Both his children, and the rest of his family live in Quebec. Whereas I have no family to speak of in eastern Canada. All that to say that nevertheless we both had good friends there and agree on a certain number of visits per year. We try to turn it into a mini vacation. One suggestion for you that I read was to find a rent to income apartment. I have seen a number of them and they really are quite decent. I am sure your son feels a ton guilt over his proposed move and that is as it should be.