BlueInanna,
I hope you can find the strength to do what you need to do.
I suck at advice sometimes so I don't know that I have anything helpful to say except that although I am new here I sorta feel like I know you a little and that makes me want to be here for you. I can feel a little agitated with your cousin's behavior and that she is not considering how her activities are affecting you...especially while you are going through your own things right now. It really is not fair that you are the one left here to deal with the business, her husband, and your own life that is all hanging in the balance.

I don't know how much is forgivable in a situation like this...
It makes me scared for her a little too; knowing how mania can make everything seem so shiny and real...

when we are fooled by it is when it gets scary; too bad it is so hard to differentiate what is real and what just seems to glitter. That is the part that I hate the most because it feels good but it isnt...
Can you try to get in the shower at least to see if it makes you feel better? Throw on some music while you are in there and see if you can't shake the funk a little...Sending healing vibes and wishes for strength in your direction.
I wish I could come help you. Sending you as much positivity as I can muster up.