Please, please,please let me know where I screwed up. Outside of the fact I’m still living  in hell. My DH feels that there should be a clean slate given to SS 16 because in his mind were weren’t bringing up the past when my kids came back from staying out of state with my family. 24 hours after I get them home SS16 is picking at DD15 about her eating- mind you we went out for a special dinner, which I told DH that SS16 needed to be on his best behavior or else he wasn’t invited, and like and behold SS16 starts in on my DD15 about how much she’s eating, how she’s gonna get kicked off the volleyball team. My daughter told him to mind his own business and leave her alone, but he kept running his mouth until she finally said shut your mouth and mind your own business, for which he calls her names... while we are at the restaurant... right under his fathers nose... and DH is completely oblivious to this. I called my DH out on his not paying attention which started a fight. The kids got the DH special of him not actually getting his son in check, but blaming my daughter as well because she made comments earlier about her being hot and sweaty, and needed to lose weight( I never heard her say those things). So the rule was leave her alone. Mind his own business. Fast forward to yesterday where I had been on call from work, then got called in only to be called off and sent home. Upon returning, SS16 has been in my girls’ room shooting the nerf gun and stirring up crap with my DD15 yet again. See the rules never changed, never did we renig on SS16 being banned from my DD15 room because we’ve had issues in the past with him causing trouble so he’s only to go in there to use the washer ( converted garage into Bedroom for 2 of my kids). So when DH comes in from work, We all have a sit down- I have already chewed out my kids because of their fighting, but was waiting on DH to get home because I feel SS16 needs addressing. First of all I feel SS16 is targeted my DD15 and is constantly trying to pick a fight with her. So while we are discussing with SS16 that his behavior isn’t tolerated, then DH drags my DD15 into the hot seat because she’s being a “grumpy teenager “ so I asked him how this was DD15 fault because she certainly didn’t invite SS16 into the room or ask him to shoot a nerf gun at her while she was sleeping. All this starts as soon as the adults leave the property. That the rules haven’t changed. I get pushback from DH because I’m raising my voice. I was beyond irritated at that point so yes, I was raising my voice. Then SS16 has the audacity to tell me and DH that I don’t discipline my kids like he gets punished. Let’s be clear I do take away cell phones and tablets for bad behavior. SS16 gets sent to his room where he has full access to his TV, PlayStation, computer... just not his cell phone. ( which I refuse to put any money on because he always shows me disrespect ) so of course I will not tolerate at entitled 16 year old to be disrespectful to me by any stretch of the imagination, so ignite and boom. So DH gets mad at me, SS16 starts using stuff from his past before I ever arrived against DH, the manipulation of DH is in full effect. So I get accused of being wrong and that I hate his son. Mind you the kid can’t respect anyone or anything and it’s my DH fault for this. This is all before I ever entered into the picture, but because I demand respect from children, I’m in the wrong because I raised my voice and fought back. Funny.. same thing happened at public school with the teachers and he got kicked out of public school twice. I get the whole talk about how I won’t let any of the past go, start treads. So when I bring up the incident from Saturday and how he was told to leave her alone, I’m wrong because we have to start from this point. The new rules. Uh wait, wtf? When did the rules ever change? He’s never been allowed to shoot nerf in the house, he’s never gotten the Ok to go into my daughters room, no rules that have been set prior to my children leaving for 1.5 months were ever changed. I feel is just DH covering for more crap his son pulls and trying to buy him more time. So since most of us functioning individuals can remember rules, where exactly am I wrong in having the expectation that those rules are still in effect and must be respected? Please feel free to shed some light here, I’m lost. I love how this all became my fault because I demand respect.