It’s not working but to be honest I feel like I can’t even get started in trying! 
My boyfriend and I have been together about five years, are in our early 40s and he has a 13 year old DD. He and I spend most of our time at my house but he also has a flat in the city centre and this is where he spends his agreed days with his DD.
For the first couple of years of our relationship he was quite compartmentalised about his life as a father. This was fine with me because I don’t have children and I love the flexibility and freedom of my life, especially throughout my 30s and 40s when I have become more financially secure, have greater disposable income etc. For example, I have always worked from home and so it is easy for me to work from anywhere.
However, over the past year or so he has said it would be nice if I got to know his daughter and that it would make some things a bit easier. This is true especially in terms of drop offs or pick ups because right now I can’t be around as DD will be “uncomfortable”.
We have tried but it almost always ends in disaster. Like she won’t even get out the car or she’ll call her mum to say she doesn’t want me to be there when her dad is picking her up from somewhere. (This so the stage we are at- just me being in the car with her for 15 minutes! The idea of lunch or going bowling or something seems absolutely impossible.) There is then some big drama with me usually wasting most of a day travelling somewhere and then hanging around while a solution is found so DD doesn’t have to see or interact with me.
So it’s like I can even get started in getting to know her and us being comfortable together.
I need someone (obviously her mum and dad!) to at least create the foundation for this to have half a chance of working. I will then absolutely do my best, but it’s like I can’t get a foothold.
Obviously there are things going on that I am not aware of, in terms of how her father’s relationship is presented to her or how they co-parent together in general. I don’t think I can get involved in anything like that, even if I do feel that their parenting style actually creates issues. My experience of parenting is from my own parents, so of course it’s decades out of date!
What would you do? I’m close to just saying, We need to go back to the way things were because it’s obviously not working and I am loathe to continue wasting days and hours like this every couple of weeks.