Oh, my GOOD-NESS?!!!?
@Velveteen Bunny - (this is almost, just... "Too Much?") . . . I can't believe what you've had to go through, and endure? I forget who said it, someone important, from the past... but it was in essence, or essentially "Life isn't fair... (get over it)." Not that--that applies in its entirety here; mind you - other than the first part/or 'half!'
Now, it is quite shocking to me, that your NIECE is acting in this way. . . Unless she is, as you say she is (& you've listed and cited some excellent examples simply illustrating her character, alone to me!). It's almost like, you'd think She was the Daughter & You, the "Niece?!?" It's really unbelievable & incredible to me, that someone could be that dense, and tone deaf quite frankly. You'd expect, or think if anything it'd be the exact opposite, or the reverse when it comes to the treatment of you (& your Mother) by her, and her family. I wonder if having moved everybody in there like that has sort of created a "set up shop?" -type "feel," or sense of entitlement; whereby, or wherein she now feels like it's her territory? I can't imagine, or fathom doing something like that my self. But perhaps if you interject all those other things (or people) into the mix - it makes it a little bit easier, to "forget," what you're doing... & therefore/then be 'unconscious,' about the entire matter? I don't know, I'm really grasping at straws because it is not something I can put my-self in a position of seeing, let alone doing (what conditions would have to be met, or need to be present, in order for me to behave in this way?)
On the podcast: Yes, I think any-thing you can do, is worthwhile giving it a shot! Even if it means cramming some of the things in your bedroom (if this would even be a possibility?) into the corner, or out of the way, to temporarily give you a "shot," of the corner of the room -- or the edge of the bed. If all you're looking or planning on doing is "talking," and not something, say more 'interactive?' I don't know if you've seen comedian Theo Vonn's podcast (he's got a bunch!). But the one he may have started out with, it just looks like it's him going or flying solo, and there's literally just like a desk there with a chair and him sitting in it. And he sort of just "talks," in monologue style, or fashion, on just about anything. I know he had a producer when he'd started out, and maybe he does have somebody there to assist him, or put it all together when it is done.
But from what I can observe, if you were to try to copy that 'style,' (& you could just watch one of his on Youtube, it's the one that has WEEKEND in the Title, something like - Last Weekend or this past weekend, ...) but you could mute the sound if that course language or style of joke telling is not your cup of tea. But from a camera setup standpoint, or point of view, it is simply just looking like a camera is placed in a static position (or fixed) like say on a table or a chair with some books, whatever is necessary to achieve the right or correct height for you, or that you like. And then I don't even know if it really moves much, or cuts (to different shots/angles) at all, really. And even if it does - it would not be necessary for you to do so, simply set up a cell phone or something, if that's all you got (get a tripod) or make a "make-shift," one. And you're pretty well done!
Glad to hear about the story with your Mother & Grandmother and/with "All the flowers!" that was Lovely - (until the end?). Sorry..
Hopefully, maybe, there's an end in sight (to their tenure there?). And if there is not--then just continue to do the best you can, and try or attempt (even in spite of their/her best efforts- "otherwise!") to ~'live & let Live.' ; ) Best wishes-