I need some opinions on this please.
P has 3 DS, I have one DD - all teens. We have been together for 13 years and all 4 DC live here full time - his DC have no contact with their mother - their choice.
Another massive row erupted last night and I want to know who is being unreasonable.
P treats his children very differently to mine and IMO is unwilling to discipline them or show that their behaviour should have consequences. After numerous incidents of him going OTT with my DD a couple of years back he withdrew from any kind of discipline or conflict with her.
Last night SDS14 wanted to download an anti virus app to his phone, saying he just wanted a general clean up - a lie, because it transpires that he had been on inappropriate adult websites and a spoof virus warning appeared which he panicked and thought was real. He then managed to reset and lock himself out of his phone. Further lied about how that happened - when pressed about it he admitted to the website. Then cried (IMO to get out of trouble, which worked, as rather than getting told off, he was then comforted by P).
When my DD went on an inappropriate app last year I put parental controls on her phone. Ps approach with SDS however is that he’ll “talk to him tomorrow” but won’t be putting parent locks on because he wants to trust him to not do it again 
Another recent incident - DD went to the park with her friends, was harassed to the point of a stranger bringing them home to protect the kids safety, and P went nuclear because he “knew that would happen” if she saw her friends (pre lockdown I would add). On the flip side, SDS went to the park with his friends, decided to leave and go somewhere else they weren’t meant to be, which resulted in his friend breaking an ankle. Rather than be told off for lying about where he was going, he cried and so P comforted him and told him how sensible he was for not engaging in the same stupid activity.
Anyway after another row, I am told that I am allowed no say in discipline because they’re his kids and it’s apparently none of my business. I think all DC living together should be treated the same. Incidentally I do 90% of housework and all cooking (which recently the SDC opted out of as they didn’t want to eat at 6, so they are now allowed to make their own food at 5) which he is happy to accept, but I have no say on how they behave in our house.
If I am being a wicked step mother and have lost perspective then please tell me because I am fed up of living like this.