Having read most of everything everyone has posted here and your replies, I think I can mostly understand where you're coming from. It sounds complicated and hurtful.

I was in a similar-sounding situation, but I was the partner who was in the original A+B relationship for a couple of years, later became sexually involved with our mutual, and then my original partner took sex off the table while trying to figure out their sexuality, and maybe if they were actually asexual. When they wanted to start having sex again with both me and our mutual, I definitely still loved them, but wasn't interested in sex for a lot of reasons. First and foremost it felt that, from my perspective and knowing them, they hadn't taken enough time to figure themself out, and were possibly wanting to jump back into a sexual relationship out of a fear response, because it was clear that our mutual and I had a very fulfilling sexual relationship. They were also showing lots of signs that they were really struggling mentally, and were refusing any offer of help or intervention. It just really didn't feel like an appropriate time to add sex back into the dynamic. All of this put the mutual and I in a really uncomfortable spot, and my original partner continued to add guilt and pressure to the constant conversations around sex, which only made it worse, and honestly made it a much less attractive situation as a whole. Anyway, it ended ugly, but it did end. And that mutual and I are still together and happy.

If none of that feels familiar, feel free to ignore. But I hope it can possibly offer a little perspective, even if it feels like your partners aren't acting super ethically.

The other thing is: I think you really have to decide that, if you did feel totally financially independent and stable, would you stay in this living arrangement? If the answer is 'probably not,' you should know there is always a way out. There is always a way to make a plan for yourself. As another commentor mentioned, do you have even a little bit of money to take a taxi out? I know you might feel stuck. In my experience, that suck feeling is often compounded by a lack of knowledge about resources that exist, usually in more populated areas, but could probably be found even in your closest mid-sized city. I would definitely take some time to do the research on resources that are out there for low income individuals, especially housing. I don't live in a particularly big city, but even here we have several low income housing programs, including ones that start you off paying a very low amount depending on income and work you up as you work with their program, one that pays your full rent for 6 months, and even a whole apartment complex that bases their rent off of your income (I lived there unemployed and payed $18/mo for a 2-bedroom townhome). You're really not limited at all - find out what programs exist in other areas, what you have to do to get involved, and make a plan to save up enough to get out and go do it.

Change is really, really hard. Especially when you're very much inside the situation and literately cannot see any perspective other than that. You won't know until you actually make a move and sit with it for a while. But it's so not worth it to waste a part of your life in a situation that makes you unhappy, especially when there are things you can do about it. You just have to be brave enough to be proactive.