What would you do in this situation?

I tell my friends that I’m going to leave her. I make plans, I set aside money, and I dream of being on my own.
Then, when I’m home I can’t get the will up to pack what’s left of my things, put them in the car, and go.
I left the house, once, for six months. But during that six months I saw her nearly every day. I talked to her every day. Then I started paying her bills until I couldn’t afford to keep my own place anymore.
I’m on a fence and this fence has spikes.

I’m not saying I’m a saint. I know I’m not even though there are a number of people who think I am. I’m pretty sure I have mental issues of my own. The most important of these is that I allow myself to be put in these situations and then I don’t do anything about it but complain. Keep that in mind.

I want to leave this situation behind me, I really do. I constantly regret letting my apartment go. I keep remembering what it was like before I had to live like this; maybe I wasn’t entirely happy, but I had a lot less to worry about.
I wake up early, around 5 a.m., so I can wake up enough to get the kids up. I have to juggle getting myself ready for work with making the sure the kids are awake and getting ready for school.
Once they’re away I leave for work. I work eight hours a day, unless an emergency comes up and I have to stay a bit later. It’s not a physically demanding job but it does take quite a bit of mental arobics. By the end of the day, I’m tired and drained.
Once I leave work I have to go to the grocery store. I walk around trying to think of something to make for dinner. Nobody ever knows what they want. It’s always up to me to figure out what it’s going to be and it needs to be something my wife will eat. She’s very picky.
When that’s done I go home and find out that the house is a mess and there are dirty dishes all over the place. While I’m work my wife does nothing to help around the house. Nothing. So I spend an hour washing dishes. On a good day I’ll wash as many as I can; a bad day means I just wash what’s needed to cook and eat.
When dinner is done I try and get the kids to do their homework, have baths, and whatever else. I also feed all the pets, clean up after dinner, and do a myriad of other chores.
All during this I have my wife doing nothing. If she needs a soda, I’m supposed to get it. If the heater is up too high I need to turn it down. It’s a constant amount of movement and I’m tired.
Then there are the mood swings, the accusations, the criticisms. And the drinking. Where I am now, when she’s not drinking she seems perfectly normal to me. Not to other people, mind you, but to me. That’s because I’ve seen her drunk. Too many times to count.
Take everything you’ve ever read about BPD behaviors. Everything. Multiply it by 5. Now you have my wife when she’s drinking.
I’ve been scratched, slapped, threatened with a steak knife, withstood verbal abuse, been cheated on, had my things broken, had household objects broken, had things thrown at me, been kicked out of the house, had my stuff thrown out of the house, pets have been threatened, she’s attempted to hurt the pets.
People, I’m tired. I’m tired of taking care of four kids + 1 kid who should be a parent. I’m doing it alone.
I don’t understand why I stay with it. I feel guilty, yes. Without me, everyone will be living in foster care or on the street. I don’t want everyone to hate me for leaving. Hell, I don’t even want to leave the pets behind.
Last night I was so tired, while taking care of the laundry, that I started to seriously think that I could get the rest I crave if I shot myself in the head.
Should I stay? Should I go? Should I ask my friends to pick up what’s left of my things and physically take me away from there?
I’m not looking for answers, I just want some kind of advice. Some kind of direction.