Should I tell my parents we need to sell our house or they need to move out?

So I've (M/29)created a terrible situation for myself and my growing family. It will be a bit of a story so that the context is all there.

In 2008 my mom was divorced by my stepdad and we moved out of state from a big 300 acre ranch house to a basic 3 bd house. Fast forward a few years and my mom I guess couldn't afford the rent anymore. She worked for farmers insurance for an agent and set up appointments and what not. She was able to make a deal with her boss who she had worked for over 20 years and he bought her a house to rent from him. Fast forward another few years and her boss tells her that he can no longer keep the house in his name and had to sell. That would've meant we all would have had to went separate ways and find a new place to live. My mom pitched the idea to me that maybe I could qualify for the house with an FHA loan if her boss could bring the selling price down enough. Me (about 21 at the time) thinking that would be a great way to keep my mom and her long time bf from being homeless , decided to go through with it and qualified just barely for an FHA loan with a gifted down payment from my Aunt. It started off alright and we continued living how we always did. We've always had a good relationship and I thought this would be the right thing to do. I now (almost 30 years old) that this was a terrible mistake. Fast forward just a couple years and I've met a girl . We love each other and had a child together. She had two boys of her own so now we are a small happy family of our own . We eventually moved out and got our own place to rent and I continued renting the house out to my mom and her bf. Also had another little boy during this time. Everything went fine until the beginning of this year, my mom informed me that she would be losing her job and wouldn't be able to afford the house and we decided to sell. A week after listing the house, my mother calls me back distraught telling me how she has no idea how she is going to afford to rent elsewhere. Then comes the idea of , why don't we split the house and we can all live together and we split the mortgage and utilities and we can save a ton of money. My gf surprisingly was on board with this idea. Mind you , my gf and my mom do not see eye to eye and do not get along . It was this moment I know I should've told her to figure something out and there's nothing I can do. But me being me (stupid), seeing my gf so heavily optimistic about the whole idea, I decided it's worth a shot. Fast forward one more time about 9 months and I don't think I need to explain that things are not working out . My gf hasn't been happy since we moved and of course neither am I. We are tense all the time and she is at the point where she can't handle it anymore .

Now I am stuck in a predicament. I'll do anything to keep my own growing family happy and support them however I must. Would I be wrong to tell my mother and her bf that they have to find a new place to live and that this arrangement isn't working? I feel terrible about kicking them out of their house , but if it weren't for me nobody would be living in the house anyways and we wouldn't be stuck in this predicament.

Any advice at all or comments of any kind will be very helpful 🙏