This is something I would say, about 90% of the posters on this site experience!   As you say, it isn't easy watching a train wreck from afar, but many, many children on the planet have shit parents and somehow it keeps turning. The difference is you are up relatively close and can see it all in hideous detail, it is obvious what needs to happen, but it doesn't.  If your step son or daughter has some time with your spouse and you, she ought to be able to bring at least a little bit of positive influence to bear to mitigate some of the worst excesses.  This is what I was saying to my DH only last night when we were discussing the poor life choices of SD24.  Other than that, you just have to disengage and try not to let it bring you down too much.  

What worked for me after years of stepping was evolving enough to grasp that all of these individuals are on their own personal journey; that in many cases the seeds of dysfunction were sown long before we ever knew these broken families; and that it has almost nothing to do with me.

Broken is the key word. When you become a stepparent, you aren't simply starting a life with the person you love; no, you are jumping down the rabbit hole to live in the detritus of someone else's failed dynamic.Your SO and their ex may have failed because of dysfunction in their childhoods; they may be Children of Divorce themselves; perhaps affected by some sort of trauma, or touched by mental illness. Regardless, they've made mistakes that have brought them to their current situation.

I happen to believe that we are in this life to learn certain lessons so we can progress, and while I love my H dearly, I've learned the hard way that it's not my place to interfere with his journey. I used to be a "fixer" and wasted years trying to facilitate closer relationships between him, his kids, and his family, but it only made things worse. I think the best thing you can do is be loving and supportive, stay in your own lane, and let what will be, be.

Very good post of Exjuliemccoy, and I would add that one's own dysfunction sometimes plays into the new stepfamily dynamic as well.  I spent my childhood feeling invisible and inconsequential, nobody cared how I felt, and certainly in the first decade of step life, this was horribly evident as well. I try and combat this, these days, by making sure I don't fade into the wallpaper for the sake of making someone else feel better.  We each have our own Achilles' heel in terms of things that press our own buttons, and it might help your situation to look closely at yours.  As Ram Dass said, "if you think you're enlightened, go spend a weekend with your family". 

They have one.  Not good ones unfortunately.  You should have no guilt in what happens with this child. It’s really the guilt. You feel guilty that a life is going so wrong for no reason. You have to understand it’s not your fault. There is nothing you can do. Just hope this kid turns out ok 

I love the serenity prayer & the boundaries books.  I found no relief in reading any books on stepfamilies, because in all honesty, even though we’re often the scapegoat, it’s not a problem stepmothers can solve. 

Keep posting! It REALLY does help to vent it out. It helps release the pressure that builds up from all the toxicity.

I have nothing more to add to what the others have, but I can share my story (detailed in my blogs if you want more depth). My DH and I have been together 5 years, married 1. I have 2 SDs, SD20 Feral Forger, and SD13 Munchkin. Munchkin is great we have a very positive relationship, she at 13 is excited about the future, college, driving, etc.

Feral Forger has always been depressed and struggled. She is on medications, drinks, and smokes pot. She llives with her mentaly ill mother, works parttime, has no drivers lisence, does not take community college classes. Her room has always ben a pigstye. And she doesnt care about anything. Her skin is acne-covered because she doesnt wash, her teeth are bad, just all bd.

I dont have to watch it because she is no contact, due to her hatred of us...

It absolutely makes sense. I am in a similar situation and I think a lot of others on this site are too.

It's so hard to watch a child in a bad situation and knowing how to fix it but not being able to because it's not your child. We just have to sit back and allow their parents to mess them up, and it SUCKS!

I don't have any answers but you definitely are not alone. Unfortunately this is one of those things where our hands are tied and we just have to hope the bio parents wake up before its too late.

I get it. DW and I chose fairly early on to keep SS abreast of the facts of his extended blended family world in an age appropriate manner.  

Facts set the foundation for a Skid to progress to adulthood with the ability to protect themselves from a toxic bioparent or SParent.  

It has worked well for us. SS-27 (adopted at his request 4.5 years ago) is a man of character, honor, and standing in his community, successful in his career and fully aware of and capable of protecting himself from the manipulative depredations of the shallow and polluted half of his gene pool.

It works.