How to explain differences to my friend I love?

I am having a really hard time right now with a girl I really like

We are both bisexual but if she is thinking about being with a girl, she will spend time chatting and flirting with girls, but the next day she might be thinking of being with guys and be chatting and flirting with guys. She swings to and from extremes. I'm different though. If I like a girl, I like her all the time and will still find her attractive even if I'm chatting and flirting with a guy. For me it's all about the individual, androgyny, and enjoying masc and fem characteristics in people, not swinging to extremes.

She is now really hurt that I have been chatting alot to a very cute guy who I work alongside, but she doesn't seem to realise that doesn't change my feelings for her
I still love her just as much and want her just as much as ever. I don't stop thinking of her when I'm with him, and I'm not trying to tell myself I'm straight. I would just feel more comfortable if I had a boyfriend and could then explore my lesbian side more, she is seeing a guy but I'm single so why should she mind ? I just wish I knew how to show her that I can like both her and a guy at the same time.