my sister and step dad need your help....(long post)

OK, I'm going to try and make this as short as I can...
No one in my family knows what to do anymore...this situation is just getting worse and nothing seems to help.
Ok, my mom met this guy about 3-4 years ago. Everything was great when they met, me and my sis loved him and it was all good. Then a few months after they were dating, he proposed and eventually moved in. Then things got really ugly. My sister was pretty quiet in it all, but oh man did I ever start fighting with him. I don't know if it was because I never really had that father figure in our hosue or what, but we were just always at eachother's throats. I was about 15 at the time. I was kicked outta our house 3 times in 2 years for about 4 months at a time. It sucked. School went down the shitter and I was miserable. I'm not really going to get into our fights, cuz they're all long and the same and blah. All that I can say, though, is that by the time I was 17, it came to the point where I was just calling him an asshole and telling him to fuck off. I was so sick of being "grounded" all the time and I just didn't know what else to do. I mean, when they asked us to do something, he would stand over our shoulders and make sure that we were doing it his way. I just down right couldn't stand him. I finally moved out and in with the guy I'm with now, and all is good with us......
BUT..........
just as I predicted.........
it's the same thing with my sister.
Before the whole family on both sides was blaming the whole thing on me. I don't want to sound like that kind of person, but I screwed up a lot when I was younger and it just became easy for everyone to blame me for everything that was going wrong.
Now that this is happening with my sister, no one knows what to do, and my stepdad really hates it that now people can see that there's something wrong with the way HE'S doing things, too. Not just my sister. All that he can say is that we are messed up kids. However, my mom has told me that even his friends have told her that in all his past relationships, the reason why they've all soured is becuase of the woman's kids.
He has his own kid, too, but has only seen her every 2 weeks since she was basically born. He's never actually lived with a kid, and the problem is that he thinks his way of doing things is the only way that they're going to be done when it comes to raising kids. There's no reasoning with him.
My mom has tried and tried to talk to him about this, and now they've almost broken up about 3 times in the last 4 months because of this. My mom can't stick up for my sister, cuz he'll leave....but if she KNOWS that he did something that wasn't fair to my sister, then she doesn't want to stick up for him, and again, he wants to leave, and my sister gets upset that no one is seeing her point.
Now, on my sister's end......she's kind of screwing herself over too. I mean, in the last year and a half that I've been gone, things have pushed her over the edge, too, but she's gotten into doing drugs and drinking (stuff that I never was interested in doing) and all that she does is complain that she has nothing and no freedom. My mom has strict cerfews....but that's about it. She always wants to be out with her friends, and she usually gets that. My mom and stepdad just bought her a horse, which she's wanted since she was 10, (she's 15 now), and that's not good enough, either. NOTHING is good enough. She has told me straight out that she hates this family and doesn't want to have anything to do with them. I've tried to stress to her that these "friends" who she gets high with everyday may seem like they're there for her, but she can't depend on that. All my friends suddenly disapeared when I was in trouble. I haven't talked to any of them since I left. Not that I haven't tried, but they have no interest in it. My sister just doesn't care. Everything is about her friends.
We know that is comes with the age, but when we do what she says, and we don't include her in family things, she whines. But when we do include her (if she'll come along), she complains unless everything goes the way that she wants it.
My step dad can't ask her to do anything with out her making a huge deal out of it. He told her that her bike tire was flat the other day, and she just called him a fucker.
I stayed with them for about a week or so, and the fights that they were getting in were WAY worse than anything I had ever been kicked out for. She constantly is calling him a gay fucker and things like that.
My mom isn't about to kick her out, and she's said that. She talks about how she went into this depression for like 3-4 months after I left. Before, I'd always come home. This time, I said no more. But this just gives my sister leeway to do more things and get away with it. She's been grounded so much, she has like a "debt" of groundings. She doesn't care anymore.
We don't know what to do. Everytime that I've sat down with her and told her that I can see where she's coming from, but she can't flip out over stpuid things (like being told that the dishes still have food caked on them after she's washed them), she seems to take it ok. I think that I'm getting through to her, and then she turns around and starts using me as a defence when she's in trouble and twists what I say to make it sound like I'm only on her side.
NOw, just this past weekend, she was supposed to come visit with my mom, stepdad and his kid for the weekend. She said that she had to ask her boss if she could have it off, and apparently he asked her to come back in a couple days and ask. She never did, but she told all of us that she had, and then when the weekend came, and she was supposed to be at work, my mom got a call from her boss saying that she got a kid to call in pretending to be her stepdad saying that they were going to visit me for a few days so that she coudl go hang out sith her friends again all weekend.
This pissed me off, cuz mow she's doing it so me, too.
Sorry this is so long, and I'm sure that I missed somethings, but those of you who are still with me, what are some of your ideas to trying to get this situation to go a little better?
They try giving her things that she wants, and she appreciates it for about a milli-second and the minute she's asked to do anything, it's back to fighting again. And my step dad refuses to change. He doesn't think that he does anything wrong. But he has to stop watching her every move. And even after an argument if finished, he carries it on and on. He never stops talking. Many people have noticed this, but he's even blown up at his friends for telling him the truth.
I know this is a hard situation, but it's not only distroying them, but it's really hurting the rest of the family, too, and we want to find a way to resolve this.

 

*BIG HUGS* Well, my situation isn't quite as bad as your, but my stepdad sounds a lot like yours...he only sees things *his* way. I mean, I've done a *lot* of work with my dad who's a contractor, so when my stepdad is working on something, I'll try to help him out...no, you're doing it wrong. Do it this way. OK, dude, whatever. A few weeks ago, he goofed up some wiring - I tried to talk to him, then I just walked away...lol. Surprisingly, I stayed really calm in the whole ordeal. I ask him for input on my college choices, which I have now come to see as a waste of time - beacuse he doesn't agree with the direction I want to take my life in. Oh well. So I just don't discuss that stuff with him anymore. Oh, well...I didn't offer you any advice really, except to tell your sister to learn to pick her battles. I mean, when she's an adult, she can move out, but since she's living with them...she might just have to learn to put up with it for now. *HUGS* I know I didn't offer much advice...I just wanted to let you know you weren't the only one in a situaion like that!

Oh, yeah...and...that drives me crazy when people watch me work...lol

 

yeah, it sounds pretty similar.
funny thing is, whenever it concerns anything that we want to do, it's usually pretty well supported. We're lucky there.
It's more when he asks someting simple like picking dog poop that he watches....it's kinda dumb.
but yeah.
thanx for your input

 

......damn.