Am i being selfish?

My father, for around 25 years now, has had leukaemia. Its one of the rarer forms of leukaemia and my mother is his main carer. My brother has mild autism and my mother and father recently moved to stafford to support him through university. On a recent brain scan they found signs of dementia in my father. My mother is finding it increasingly difficult to cope under the pressure and I am seriously thinking of moving closer to her to support her but my partner isnt so shore. We both have good jobs here, friends and his family. He seems reluctant to look into the idea but i dont want to leave all this on my mother. Am i being selfish asking him to give up everything?