Hi, I'm very glad that even with your broken arm, you managed to type so much, I know how much it must suck, hope it didn't hurt or anything in the process.
I'm also happy about how you took my contructive criticism. And about the art stuff, don't blame yourself for it, although I wouldn't recommend for you to try and do everything, try and diverge it, you said about your friend but for exemple, why not also do in your patreon, asking or doing a contest for some assets to be in the game? Heck you could do it right here and I'm sure your e-mail would be flooded with it; you could allow for it to leave the signature in the asset and, I mean if I was good at it, I would do it, it would be so cool to see a dope art of mine with my signature in it and in a game I love to top it all off. Still for an amateur you should be proud of yourself, it is already above avarage from most amateurs games, especially considering that you do it all basically.
I don't judge that you have those possible mental problems, after all I date a esquizofrenic, so perhaps that made me question why it felt too bipolar (and maybe why I like the yandere and maniputalitive nature of the game), still, I wouldn't say it is a bad thing for it to be like this in the game, after all as you said it is meant to be like that, however - and I assume that is a hard thing to do - just because it is meant to be like that, doesn't mean it shouldn't be deepened; maybe in the best friend route with her questioning the MC and/or Castor(ia) about their seemingly bipolar way of talking? One way to make it more natural is to put a bit of yourself in it, as a player of D&D and other RPG's, I do this a lot of the time and it gives more vividity (I assume you already do this, but well it doesn't hurt to recommend).
And story wise, I'm glad to hear all of that and I'll put my faith on you. That being said, although that is for you to decide, I wouldn't recommend for the other routes to be completely disconected from one another, for that each route would be to have way good and deep on it's own, wich sure it can be nice, but I would argue it is way harder to do, by making it conected, each route can enhance each other by adding details and perspectives, also giving the sence of a cohesive storytelling and a clear image of what the game is about, the only problem is if it feels forced cof cof disney star wars films.
Well, about the problems with gaining money, it must suck, I live in Brasil and I don't know the rules for those kinds of supports nor how to cheat the system, however can't you use someone to bypass such a thing? for exemple, you are working with a pseudonym, so if you made a bank acount in your (mother/father/brother/psychologist (yes, really)/family/etc) name, it wouldn't trigger the government, the system is very balanced with no exploits, so try and search for ways to exploit the hell out of it, and don't feel sorry for asking your psychologist or anyone really for this kind of help either, they will understand.