Adult Step daughter still lives at home

[Lamppost]

I have been married to my wife for 7 years. She has kids from a previous marriage. The oldest is 21 and still lives with us. This adult child has no desire to do anything. Won't go to school for anything nor get a job. Wants us to buy things for her constantly and we have a pretty low income currently because I just started my own business.  We must drop whatever it is we are doing to do whatever she desires or we get pouting, rage or I will hurt myself. Refuses to get a driver's license so we have to take her every where. No friends and wants our attention all the time especially at night she seems to always have an issue we have to deal with even though we have the rule everyone in their room at 11.  I am a person who likes to joke. She's good for a while and jokes back but one wrong step and the world is ending and it's all my fault she is miserable and worthless. She states she was molested as an infant and remembers it all. Blamed her bio-dad then changed it to someone else. Still won't have a relationship with him but certainly takes gifts from him. I'm to blame she has no friends because her mom moved in with me and they moved a few hours from their original city. Did online high school because regular school was just too much for her. My wife drops everything and does what she wants when she wants it. She feels guilty this child is miserable I think so is trying to make up for it. She's getting better with boundaries but we pay for it. Adult child says I just don't understand she's way sicker than I see because she hides most of it. I do understand because I am a licensed counselor.  It's so much different living with someone diagnosed with BPD. But I have known since before meeting my wife I don't have the ability to deal with BPD and I refer them to someone else.  As a counselor I see exactly what is happening but I can't do anything about it because I will lose my marriage over it and I truly love my wife and will do anything for her. Adult child is so arrogant and loves to tell us what to do and why we are always wrong and how to parent the other kid. She goes to counseling but has had several and always changes when they tell her she needs to try and get a job.
I'm completely exhausted and so is my wife. My wife has several significant physical problems including having seizures because of stress. (And we have lots of stress) I have some physical problems but I'm not sleeping and things are just getting worse. I'm dealing with my own emotions because my mom just died and my dad is not healthy and probably won't be here much longer. I was having a particularly bad night about my mom and she knew it but came to my wife and I about how we hurt her for moving her with her not getting a say at 12 years old and whatever else she could pull from the past. I had to stop mourning for my mom to deal with her BS. I have tried to find counseling for me and my wife but everyone so far is full.
I am pretty much done with this child but I don't want to just leave my wife to deal with her alone nor do I want to lose my wife. But I'm losing my ability to be happy and losing myself because if we even try to do self-care she interrupts it in whatever way she can. We can't even go to the store ourselves without her having to go. We have to get up ridiculously early to go before she gets up. I'm tired of walking on eggshells. I feel like a prisoner in my own house and mind because I can't talk to my wife about it unless she's really pissed off with her. I don't know what to do because I want to be with my wife and not leave her to deal with her but I don't think I can deal with this much longer. We do try to do boundaries but we're just so tired of this it's just easier to do what she wants. As I said I am trying to find counseling for my wife and I but if anyone has any suggestions I would be incredibly grateful!

Our objective is to better understand the struggles our child faces and to learn the skills to improve our relationship and provide a supportive environment and also improve on our own emotional responses, attitudes and effectiveness as a family leaders

[Tanager]

This is so tough. I just wanted you to know I relate so much to the pain you are experiencing with your daughter.  My family's problems - husband's cancer, aging mother's health, other family members ' needs,  - the list goes on - all of this takes low priority to our daughter's latest crisis.  We have all learned to avoid mentioning even having a headache because she will develop a migraine!  We are getting older and the stress is taking its toll on both our health and relationship.  I do know taking just a few minutes together with your spouse helps a lot, if you can somehow find a little time. I guess I am lucky because my daughter hates grocery shopping!  I know there are others who can offer you words of encouragement and good advice, much better than mine. Just wanted you to know that you aren't alone.

[Lamppost]

Thanks Tanager!  I totally forgot about not mentioning physical stuff like a headache because her's is always worse.  She always has something physically wrong with her and it's goes from having a little tingle in her toe to she has cancer and going to die. I am so frustrated and I feel there's not a thing I can do about it. She diagnosis herself all the time and gets to the Dr, he runs tests and nothing.
Going to the store for her is great because she can get stuff that she doesn't need but wants and it's not cheap either. She has to have these clothes and then a few months later they are at Good Will and now she has nothing to wear so has to get new clothes. She seems to think we are billionaires. But going to the store she can also publicly ridicule my wife and I or she will have a dramatic panic attack. If she knows we are going anywhere she wants to go. I really partly think it's to annoy the PLEASE READ out of me. And it works. Her mom will make me take her places so she can "get out of the house" and she will promise not to annoy me but does it every single time. And I say never again and yet I still have to take her.
She's never going to leave this house because why would she? She can't afford to live alone and is doing nothing to even try by getting a job or school because she's too sick for that. I feel like I'm going to an early grave if I have to keep dealing with this. I get it, it's part of the diagnosis but I can't keep this up for years. I honestly don't know what to do. I do appreciate you talking to me though. I'm so glad someone else gets it.

[Tanager]

I hope things are going a little better the last few days and that your dad's health has improved. I know I have been there as much as possible for my elderly mother, but it never feels like enough.  My daughter's needs take so much time and energy!  I feel guilty and also depleted. I understand how you haven't been able to truly grieve as you need to for your mom and also focus on your dad.  Let alone focus just a little on yourself.

It's hard to find time for oneself to relieve the unrelenting stress. Three things that have helped me are exercise (even a walk around the block), being outside (my daughter hates yard work so I get a little quiet time), and meditating (lots of free resources online and even 10 minutes makes a difference).  You may well have tried these ideas and more, but thought I would mention them.  Best to you and everyone on this difficult journey.