I'm so tired of being the scapegoat...

I guess this is just a vent more than anything. I used to have a great relationship with my SK's but for the past few months it's been pretty rocky between SS (10) and merely. To sum it up, SS would tell BM he didn't want to come over because of various different reasons relating to me. Every minor thing I would do that he didn't like got scrutinised. I felt like I was walking on eggshells. Despite always doing my best to make sure he was happy here, it wasn't good enough. In the end, I totally stepped back for my own mental health. SS and DH had some chats and things have been much better lately, but I'm more of a friend than a parental figure now.

On the days we have them, I tend to plan activities for me and my bios, but as SD (7) and I are still very close she'll usually tag along. She's been having some struggles herself lately missing BM (she works a lot of evenings/weekends and has a new partner) and SD is finding it hard being away from her. We only have them EOWE Fri - Mon and every Weds evening so BM's is the primary household. Today I was dropping SD off to her grandparents for an activity they'd booked but instead of getting into the car she skipped out into the road and my BS (2) followed her, as he always does. I told her not to go into the road, BS would follow and it was dangerous. She got in the car, we had a lovely chat, I dropped her off. BM shows up to the activity unannounced and suddenly SS no longer wants to come back and wants to stay with BM because I 'shouted' at her. I didn't even raise my voice. I didn't discipline her.

DH is great and fully has my back but honestly, I've had enough of it. I get they might have feelings they don't always understand so I try to be supportive, I try to be a positive figure in their lives, but it feels like I'm always being used as the scapegoat. How am I supposed to feel comfortable around them?