the partner that your mom has had for 18 years would not care for her if she were ill?
He certainly wouldn’t just abandon her, he would do something to make sure she is cared for. He absolutely is a good guy in general. But I wouldn’t want to rely on his measures to care for her alone, simply because he is not the most caring person by character and their relationship isn’t as close anymore. They moved out of their apartment after 16 years into two different apartments, in the same building but still it shows their distance. Most of his vacations he does with friends and not with her. They have more of a platonic relationship by now than a romantic one and he is generally not the type who would sit at her bedside the whole day and feed her. He has enough money to hire someone to do it and would visit her, but that’s not the kind of care that I would want for her.
And even if he would care perfectly well, personally, for her, I would still want to be there for her in any case. She’s my mother, I love her.