Forgive my English. 

My girlfriend and I have been dating for almost 3 years. She has BPD but her symptoms aren't as bad as some of you guys'. She doesn't go to therapy. She should. We've had some very difficult times but we've managed to keep the relationship going relatively well. 

Our sex life is amazing. She's not kinky and neither I am, but somehow our sex life got a bit kinky. A bit of dominant/submissive, where I am the dominant one. I like it because she likes it. She likes it because I like it. It has been progressing a lot. There isn't any pain or anything like that involved, but there are some control things. She hates being submissive, but she wants me to want her to be. It started with me calling her some names and now it's come to me making decisions for her. I'm not comfortable with that because I really value independence in my relationships but I have started to like it too. She finds comfort in me being an almost parental figure in sex. I find comfort in making her feel good. 

I'm scared that this will progress more. I don't want to become a controlling asshole. I don't want our relationship to turn into only this power dynamic. We are equals but sometimes it is starting to feel like we aren't. I'm scared that she's using me to not deal with her problems. I'm scared I'm using this because it helps her feel like I'm there for her and there's no fights. 

I like this dynamic sometimes, but I don't want it to go stronger. I don't know how to tell her because she will feel like it's rejection. She's an adult and can deal with thigs, but I hate being the one to trigger bad feelings. 

Does anyone have any recommendations on how to approach this?