S.,
I can completely relate to parts of your situation, as I, too, live with my father (who just turned 81), along with my daughter, who is 10, and my fiance. One difference is that my daughter and I have lived with my dad since she was 1-1/2. Privacy for EVERYONE can be one of the biggest challenges to deal with in a multi-generational home, along with a clear sense of who has responsibility for what.
As far as your son is concerned, the first question that comes to mind for me is this: why are you sharing a bedroom with him and not with your husband? I don't say this to pry, but I wonder if much of the frustration your son feels isn't due maybe to the fact that he has no personal space of his own? It's fine for us, as adults, to look at the situation and nod our heads knowingly and acknowledge the difficulties inherent with the living situation you describe. But a child cannot possibly understand this, nor buck up and deal with it for however long it may last. Since you say there are 4 bedrooms, wouldn't it make more sense to have your father in one, your mother in another, you and your husband in a third, and your son in his own room?
At 4, your son needs a structured schedule that includes a regular bedtime that is quite different from yours. If you are putting him to bed at, say, 7:30 or 8:00, and you come to bed later in the evening, I might imagine that the process of you retiring for the evening could be disruptive to his sleep. We all need structure; very few of us function well without it. Even if he's not in school yet, it's important for him to have the same bed and wake times every day. It never fails that if my daughter is off of her routine, even at the age of 10, I can expect some of the WORST behavior possible! It's like she's a different child, and evil aliens have kidnapped my sweet little girl and replaced her with a snarling, snapping, mean little person who, I'm convinced, is going to start shooting pea soup a la Linda Blair out of her mouth at any moment! I have to grit my teeth in order to stifle my automatic "Oh, no you didn't!" reaction, but my response generally is to send her to her room to calm down...a place that is hers alone, where all of her things are, and where she can feel as though she has some control over her surroundings (even when she really doesn't).
Hang in there, S.! Are there any local play groups you could join with your son where you might meet other moms your age? Another great place to meet other parents is at church -- any church -- and there's usually no fee to get in! If you don't already have one, there's sure to be one out there that might suit your beliefs. Many are non-denominational, and might be a good place to start until you get a better feel for where you'd be most comfortable. I'm not sure what city you live in, but there's a non-denominational church in Livonia that has a really good kids program. I go to a Congregational church that also has a very strong kids program. In my experience, being part of a congregation not only helps us to share our beliefs with our daughter, but it's another part of our family structure that's vital to our mental well-being.
Sorry this is so long. I'm an English major...I'll use 200 hundred words to say what could be said in 20!
Good luck,
S.
