I can totally relate to this as far as hiding in the bedroom goes! I mean where on earth can you go to get some space and privacy! I also don't have my own kids and my partner has 2 daughters who when it comes down to it, do like me. The youngest however, has many issues and I do feel for her, but she drives me insane! The oldest lives with us full time now as she finishes her last year of school - she is fine...just the usual lack of helping around the house, but otherwise she is a lovely girl. The youngest, who can also be sweet and is desperately insecure is like a jeckyl and hyde character. She needs constant support. She demands her fathers attention the whole time she is with us. Due to some problems that are now snowballing into her not turning up to school, she is spending longer periods with us and not her mum. After the first week of this change over, I have found myself sleeping in the spare room (away from all the other bed rooms), have been bickering over small stuff with my partner, am totally grumpy and cannot stand to be with this girl!!! Her own mother also is driven insane by her and abandons her. I feel so bad that I am pulling away too!
It is extremely hard doing what we are doing. No kids of our own, and living in with our partners who have children whom we are forced to have a relationship with. I find it so difficult sometimes to come to terms with this situation. I feel concerned that any negative impact I have will scar them for life! That they will grow up with horrible memories of the grumpy girlfriend of Dad. At other times I think, I don't know if I can do this relationship if it means having to deal with children that you can't really have control of (as in their parenting). I don't know what to suggest to you other than what I resorted to the other day, which was to go visit my friends and spend time with them when it was all too much. My partner was at home dealing with his youngest who had acted out on the weekend, got drunk and ended up in hospital. In the days prior to this event, I had been trying to arrange some time for my partner and I to meet up with my friends (a couple with no kids) so we could have some rare time together. In the end I just decided I had to let go of that and that the best thing for me to do, and in a way to manage the difficult feelings I was having towards his daughter, was to take my self away for the day and have some fun. There are no rules that say you have to be there with your partner all the time when his kids are around. It sounds horrible, and for the sake of your own relationship, you may need to find ways to take care of yourself to better deal with it. I hope that helps.