How'd I end up so bad at this?

I don't know what to do. Pat's pissed at me. Caitlyn apparently hates me and the world in general. My kids are disrespectful and rude, especially to Pat and secondly to me.
They tell him he doesn't belong here and no one wants him when he repeatedly asks them to do things and they ignore him-he loses his temper. I do too.
Caitlyn has issues. I don't know what the hell they are. She won't talk to anyone. Me included. I'm fairly sure I'm failing at this.
How do I fix it? How come they hate  me so goddamn much?.
The little kids are even starting to be jerks to everyone. They see the big kids do it, and since Pat never disciplines them-he makes me do it when I wake-the littles figure it's ok. Hell Jo even asked if he's her daddy. Emily screams all the time. I never sleep anymore because of it. I'm past the point of exhaustion. I'm physically sick most of the time. But I have to suck it up and keep going because no one else is bringing in money.
We are stuck at my parents house because we can't afford to live on our own, what with only one paycheck and all.
We won't ever get out of here. I know that. We're stuck in this pit where no one but Pat ever cleans up, we can't get ahead and we can't even argue because my mom tells us to shut up.
So everything simmers under the surface. I seeth. He's pissed. Everything is on me: money, bills, discipline. All of it. But I'm not allowed to be annoyed or upset or anything. I'm just supposed to keep doing it.
I don't even want to see my friends anymore, or talk to anyone. No one cares if its hard. No one has any suggestions that work in my situation because they don't live in it.
I'm a horrible mom and I know it. Even if no one believes me. I try, but I suck at this. And I doubt its going to get better.