I've been in a similar position, but at the time I wasn't dx'd myself yet. I also think it can be worse at times, as women do tend to be more sensitive. Add that to BP that might not be totally under control yet, and it can be a real problem. Take this relationship slow. Don't dive in too deep until you fully understand her and can really talk about her BP. It sounds like she isn't in control of herself.
Mania can really hurt you badly. She needs to be open to being in a relationship and needs to see how she hurts you at times. Don't give up on it - just don't throw your entire heart and soul into it, because it seems like it is being thrown back at you every time she's manic.
And it's totally understandable that you weren't ok with the ex staying over - you were almost TOO civil about it