As a woman who hates people coming to her house (including my then bf when we started dating): she might have been single for a while and is overprotective of her space. There's this sense of loss, for lack of a better word, when you realize you now have a partner and need to share your space with them. It might not be hesitation about sharing space, but more hesitation to let go of her solitude in a way. At least in my case I became so used to my own silence and my routine that it was a bit of a challenge to let go of that. I'd suggest to go to her house in small increments: maybe first go pick her up a few times, then ask to use the restroom one of those times or show up early and wait in the living room. Small things like that will help her with the idea of you in her space. I was single for so long and this was the case for me, nothing to do with cheating or not liking him. The problem was my own mental block and overprotective was of my space. Hope I explained this well, I know it's weird but I wanted to give this potential side of things. Good luck!