Op I was physically abused for many years by my dad, not sexually, but beaten black and blue. When I go home to my DS and my DH (SAHD) every evening it doesn't ever occur to me to check his body for bruises or abuse. My husband is a different person, in a different situation. I have an old work colleague who was sexually abused, along with her sister, by her grandad, whilst their mother was in the next room. Your DH quoted that he would not "sleep" with her. My mates GD didn't either, technically that wasn't a lie, he would stroke her inappropriately when she went for a cuddle and once tried to insert a rolled up newspaper into her. I could cry now just thinking about the day she told me. She and her sister, never EVER told their mother or father. They are now in their 40's. Thankfully her older sister recognised the abuse from her earlier experiences and protected her sister by refusing to let her stay in the same room as her. She is now married to a wonderful trusting man and I know she has no suspicions or doubt with him and her DD EVER.
You are checking your daughters for sexual abuse and you've mentioned upstream that you have already had counselling as pushed by your DH. Do you think you have received enough counselling for your historical issues?
Please don't think people are ganging up on you, or calling you stupid, if you were that, you'd be blithely carrying on wouldn't you? You chose to post on here because you had concerns. What you posted was very worrying, can you see in hindsight how strange the majority of posters found that your DH was cosleeping with his teenage step daughter?
I hope you can get some resolution out of this, I know we don't know the whole story, but I am grateful that you called the NSPCC and hope they gave you some advice to deal with this. I would be looking at RL 3rd party help mainly based on some of the "ideals" your DH has from his "therapy". Do you have a RL sibling or friend you can talk to, or even your GP? I know there is a worry with gettign offical involvement that your whole family could be ripped apart, but the family life you have now doesn't sound healthy at all.