Tired, frustrated, and at the end of my rope

I am a MotheringDotCommune lurker and have gotten so many great things from this website, but I never post...so here goes

I have a 5 year old, 2.5 year old and 7 mo. old in a tiny 2 bedroom house. Nobody sleeps. Let me repeat: Nobody sleeps. My 7 mo. DS wakes every 3 hours on the dot for a little nurse and then usually goes right back to sleep. Doesn't sound so bad, but I'm sure as all of you know this constant waking leads to exhaustion over the course of months. He is sleeping in a pak n play in our room while the other two are in bunk beds in the other bedroom.

So, I may be lambasted for this on this forum, but in a state of utter desperation I let him cry for a few nights. Didn't work, so we're back to nursing every three hours. However, if I don't get to him right away and he cries my 2 yo DS has started waking at a pin drop through the night. It's comedy really : I nurse the little one and then head down the hall to see what's wrong with our 2 yo. and sometimes on a really hilarious night my 5 yo will wake screaming that she can't stand the baby crying. Oh, and then my husband will get in on the action. He's a bear in the middle of the night and I'd rather he'd just stay asleep then try to communicate with me. We usually end up screaming at each other and the whole house is crazy!!! We've always started our babies in the family bed for about six months but then they've always moved to the crib with no problem. Our 7 mo. doesn't sleep any better in his own bed or in our bed. In fact, I think he tends to squirm and wiggle more in our bed. We play musical beds at night with everyone. We've even tried sleeping in the living room for awhile.

Needless to say, everyone is exhausted. I can't handle tired kids during the day and I cannot see this ending anytime soon. We've tried everything and it comes down to me getting frustrated that our house is so small (you can hear everything even with fans - lots of fans) and we can't afford anything else, because we have chosen for me to be home with the kids instead of out working. Then I think, we can do this. I don't need a bigger house. I would be perfectly happy here if we could just get some sleep at night.

And honestly, my husband is not much help right now. We run our own business and he's just trying to stay afloat while being exhausted while at the same time I try not to scream at the kids while being completely fatigued. <-- This sentence is funny - obviously I'm tired. We don't have a lot of help because a. babysitters are not cheap and b. family does not live nearby except my sister who is busy with her own life.

I hate to boo-hoo like this as I have been trying to stay positive and visualize what I want our nights to be, but I'm feeling really low this morning as my house is a wreck and we're about to have a playdate over with kids that I'm not crazy about.

Thanks for reading. I don't even need any responses. It just helped a little to write.