I feel like a horrible person but.....

Where to start? The MIL and I haven't gotten along since our rehearsal dinner over 10 years ago. It was all the normal things from her like I've seen on this page. "You're not good enough for my son. You could lose weight if you tried this pill. You should try this fertility tea..." You get the picture. Now she has got Ovarian Cancer. She won't tell us what stage, but it has spread all through her abdomen. She says she's got a 2.1% chance of survival with chemo. One problem, she won't do the chemo. She went on this long rant about how it's a big conspiracy that the drug companies use to kill people and on and on. It's insane. So she's doing this Hypothermic therapy (she's basically going to cook herself) and according to her "research" (i.e. the seller of the therapy's anecdotes and her boyfriend's BS) she will be "cured" by Christmas. We did 5 minutes of research online and the whole thing is a fraud unless it's done in conjunction with Chemo. She won't hear a word against it and won't listen to her doctors or anyone else. I think she's doing this for a sense of control, but I know this isn't going to work. And when it doesn't work, then what are we going to do? Now for the rest of it, she's disinherited all of her children. She's giving everything to her boyfriend. We don't want anything really, but my DH is really hurt by this. It's like she's chosen her boyfriend over her children. She's actually told me "It's not like I've got any grandchildren to leave anything for". Ouch, we've gone through the whole fertility thing, it's not like we haven't been trying and she knows that. Now she's refusing the at home nursing care we set up for her. After hurting my husband she is expecting us to drop everything and dance like her puppets. We live 3 hours away, it's not a hop, skip, and a jump to get there. She called tonight and said "you'll be here at blah blah blah time tomorrow." Not asking, not inquiring, I've got to work tomorrow so there is no way I can get there on her schedule and my husband has to work on Sunday. So he'd drive all that way to drive back. But, she shouldn't be left alone either. She can't care for herself anymore. She can't even get to the bathroom by herself. Her boyfriend won't take anymore time off work and he doesn't seem to care that she's alone while he's gone. Her friends have been coming by when they can, but they can't stay forever. We've talked to the hospital and there's nothing we can do. She's competent to make her own choices, albeit she's making bad ones. Has anyone else gone through this? What do we do now? I'm just so stressed out about this. It's bad enough that she's got cancer, but does there have to be this kind of drama on top?