I am single, but have a main girl and a couple of side girls. My main girl is a very good friend, and one of my side girls is decent. The other side girl wanted to be my girlfriend a few months ago, which led to maybe 2 months of nastiness and coldness between us. I think she has accepted that she's just my side girl, and we get on well. Having said THAT, she still gets jealous of several other girls that I know. I don't think she has a right to be jealous, but she feels differently. How should I deal with her?

Flatter her? Stop having sex with her, and just be friends? Block her phone number? Explain to her why I don't want to go out with her?