what to do when you keep getting pushed away on top of dealing w/paranoia

hey all, this is my first post, didn't think i would need help but i guess we all do at one point or another. so to be as brief as i can, i'm the oldest of four, i have three younger sisters, the one closest to me in age, deb is an rn who had been working for of all things hospice. my father passed on years ago so it is just me, my mom and sisters. four months ago by accident they found my sister had cancer that had spread to the point, well it was too late. nonetheless she decided to try the whole routine but no miracles this time. she got let out of the hospital again, this last time on christmas eve and has hospice care at home now. it is only a matter of time now. why am i posting? because i don't know how to deal with the situation. growing up we were always close, not so much later in life but still pretty close. fyi she 44, me 46. when she was first diagnosed and in decent health i tried to get her to take a drive with me up to the mountains, not a long drive two hours and at that point she was in good enough health she literally a week later drove seven hours straight, alone, to see one of her sons in nebraska. but she wasn't up to it to go with me. a few weeks later i asked her if she wanted to go into town and then it was i have too much to do i can't. i stop by she is too busy to talk to me and would send me away. i tried to help in other ways, ways where she couldn't push me away. i got her some hats because its winter here and it gets cold when you don't have any hair. she didn't want any of them. i got her flowers to brighten up the space in her house, she didn't have room, she gave them to her hospice nurse. in the hospital she begged me to get her a living will and power of attorney so she wouldn't have to worry. i did exactly that, had my mom take it to her. she exploded on her, thought i was trying to take her house and meddle in her business? she entirely forgot it was she that begged me to do the medical living will and power of attorney and besides they had nothing to do with her house but to hear say that stung and hurt, a lot. i maxed all my credit cards, brought out family so we could spend one last christmas together. i'd worked on this for months so that she and the kids could have a good lasting memory. two hours before we were to get together she thinks we are trying to manipulate her and there is no christmas. hurt feelings and crying instead from my mom and the rest. i just went over a few days ago with some mini ben and jerrys, those three bite containers since she has such a hard time eating anything at all, she gave them away, walked right past me, didn't even look at me and went in the other room. i've had my share of health problems and i've almost died on a couple of occasions so i can understand a little of what she is going through but not the cutting off of me,the paranoid ideas directed only at me, it is like every single negative feeling she has is all directed at me and nobody else and i don't know why or what to do and it is killing me inside. tonight we are going to get down around -20 so i made mention to one of the kids to pull the gps out of the car so it doesn't get damaged by the cold. she turned almost, forgive me but evil on them, and told them,"you tell michael not to worry about his gps and to mind his own business." i don't know my sister now, she has pushed me out, she doesn't have time for me, and even when i do things she ask of me she gets paranoid and thinks there is some other motive for doing it? like the gps thing, i could care less about anything material at her house i just wanted somehow be a part of a conversation without it having to do with anything medical. i've volunteered so many times to take her to appts. yet she always turns me down through others or doesn't return calls. she would rather go with strangers than me. we were good, we were okay before she got sick. i have always been there for her growing up, and now she not only won't let me get close i am the focus of ever negative paranoid thought and it is the most awful of feelings. i am at a loss, a total loss. i know there are no easier answers but i was hoping at least i'm not the only one who has gone through something like this because at least knowing that would make it easier to cope if you know what i mean. so anything you have to say, anything at all, it would be appreciated. i'm just desperate and am grasping for straws at this point. thanks for reading even if you don't have anything to say. mike