I just kind of feel like as a step parent I bend over backwards to make DSS feel like a proper part of our family, including spending a lot of my own money on him (DH out of work - I pay maintenance) and we get the bare bones of a relationship where we are expected to suck up any changes at their end without complaint, don't get to see him on Christmas day even though it actually fell on our weekend, have to live with one rule for them and another rule for us.
I just typed out a very identifying rant and deleted it, but I feel really upset about this at the moment. We generally have a really good relationship with DSS' mum, but the reality is, is that DH has no control over where his son lives, where he goes to school, what happens with supposed 'medical' conditions. The only co-parenting that happens is when ex and husband don't want to/know how to discipline DSS so it falls to DH to have a go at him about something he is getting third hand from ex!