I am so sorry that you are in such a bad place right now. It is hard to understand why someone you care about can treat you so badly but most of the time there are reasons for it and the person who does it is not really aware that he has done anything wrong. You say your s/o is in failing health and this is just a guess but I bet your he is very frightened. I am not excusing the behavior but I want you to know that it is not your fault. If you don't want to go visit any more then stay home. Maybe he will call you and want you to come back. If he does then you need to point out the reason for you staying away and maybe he will understand and things will get better for you.