Boundary setting in unhealthy relationship

[HusbandAndStepParent]

My wife and I are struggling in our marriage and I’m looking for perspective.
We’ve been together six years, married for three. I have two stepchildren from my wife’s previous marriage. When she divorced her ex-husband, his behaviour led to three criminal convictions for domestic abuse and a ten-year restraining order (three years still remaining). The children have no direct contact with him and there are court orders in place to support this.
I supported my wife through everything, the years of court processes and its aftermath. The children were understandably traumatised, but with a stable home and counselling they’ve come a long way.
The current issue is my stepdaughter, who is nearly 16. My wife struggles to enforce boundaries with her because she fears she may self-harm - that has not happened so years and her biological father used to talk about suicide in front of her when my wife divorced him.

Examples of what’s happening:

• She walks in and out of our bedroom (and her brother’s) unannounced at any time & treats it as her room.
• She effectively claimed my wife’s iPad and MacBook after borrowing them, and my wife didn’t challenge it.
• She pushes for friends to sleep over multiple times a week and wears my wife down until she agrees. I can’t relax at home and my wife’s solution is to push that onto me to get out of the house more, or to move out but we stay married.

I feel my wife won’t address this behaviour and won’t support me if I try to set reasonable boundaries. When I do speak up, I’m seen as controlling or unkind.
This has brought us to the point of divorce. From my perspective, my wife’s relationship with her daughter has become unhealthy and is creating a difficult home environment, but my wife is resistant to changing how she handles things.
I don’t see a future for our marriage if this continues. Has anyone experienced something similar, or can offer advice on how to approach this?

Put locks on the bedroom doors.

But honestly if she is asked to choose between you, you know which one she'll pick don't you?

I'm not asking her to pick. She's not happy with her daughter's behaviour either, wants boundaries in place, but does want to be the person to do it.

YANBU but I have seen this before. If your wife refuses to set boundaries and parent her DC in a sensible way then sadly there is not much that you can do about it. Either she does it herself or lets you do it. If nothing happens then DD will grow up very entitled.

It is time for a very sensible talk with your wife, where you both listen to each other about the issues and decide what should happen ongoing.

I think if she wanted to set boundaries she would. It sounds like she’s trying to please you by saying she wants to, because you’re the one that’s unhappy about it.

My kids have ‘claimed’ our iPads and stuff in the past. We’ve not challenged it because we are not bothered about it. It’s your wife’s stuff, not yours, so 🤷🏻‍♀️

It’s normal for teens to have friends stay over. We had rules like homework had to be done, the other kids parents were ok with it, they tidied up the kitchen after themselves etc. It’s part of having teens imo and it’s their house too. Why can’t you relax, just carry on as normal. What can’t you do?

I wouldn’t stand for walking into rooms with closed doors without knocking, but if the doors are open, then it’s fine imo. If she’s opening closed bedroom doors, she needs to be told not to. Locks if necessary, but I’d really want her to understand that everyone gets privacy if doors are closed.

It's more than just being a teenager. My wife is afraid to confront her because of the imagined consequences. Locks on doors etc is avoidance and acceptance, not problem solving, and will make the problem worse for us and the daughter in the long run. Modelling the behaviour that you can go and do whatever you want until someone explicitly bars you is a bit odd and neglectful parenting IMO