I find this thread mystifying. DsCs mother can’t control what goes on with her DC when they are with their father (with the exception of abuse etc). She can raise concerns but that’s it. When you separate as parents you lose control — that is one of the serious consequences of family breakdown. It’s hard and uncomfortable but inevitable.
Threads like this reveal why it’s absolutely impossible to be a SM, and why relationships with DSCs mums can be so fraught. When my DSC are with us, we function as a family unit. How damaging to them would it be if I continually drew distinctions between them and our own children? I’m not going to make tea for my DC but not DSC, I’m not going to hug my DC but not DSC, I’m not going to refuse to babysit half of them when my DH (occasionally) is away/out for the evening. SMS parent not because they are weird people overstepping boundaries but because when you have SC in your household you have to parent them, it’s simply not practical to do otherwise.
Ive been with my husband for years now — the idea that my role is analogous to that of a professional at school or a random babysitter is ridiculous. Mothers might wish that was the case but it just isn’t. I spend every weekend with my step children — we have a relationship. I’m
not their mum but I’m not just a random adult either. I think Mums understandably get jealous, but it is up to them to control that impulse. A good relationship with their SM is absolutely essential to SCs wellbeing, as is a sense of being welcome in their Dads home, and treated equally to the children who live there permanently.
I have moved jobs, cities to facilitate my husbands relationship with his kids. They have affected every single stage of our relationship, every single stage of our lives. My life is so much more exhausting and complicated because I am a SM. But I’m kind, I’m accommodating, we put their needs first because they are children, we work hard to build up a family unit under less than ideal circumstances.
On the topic of co-sleeping — I would hate this so it wouldn’t happen. I’m fairly strict and value our space as a couple. However, our SC while in primary always came into our bed in a Saturday/Sunday morning. I didn’t love it, tbh but it wasn’t inappropriate — we were dressed, my DH was there. There’s surely much more risk when SC are left alone with their SM? And many parents leave their kids alone with completely unrelated adults for various reasons (babysitting, clubs, sleepovers). We’re a family — that’s obviously so different to how I’d relate to children in my professional care. I respect my SCs boundaries but equally I’m not going to reject them when they come for a hug, or want to be with my DH in the morning.
When there are kids involved break ups have consequences — and one of these is potential step parents. If you don’t want this don’t have children with someone you don’t want to be with long term, or don’t split up. My DHs ex wife left when my younger SC was 18 months. I find it totally mystifying — why did they choose to have him when they knew their relationship was on the rocks? Why did she leave when she finds my presence so hard?