If this one girl is seeing this guy and it bothers you then you may look at your choice. There is nothing wrong with dating two people so you have to make up your mind but she is clearly going to try you both out for awhile. If she can't stop thinking about you then this really is a mixed signal. You have to ask yourself if you are up to putting up with guy #2. She seems like a person only interested in playing the field. Is that what you want. You may explore the possibility of girl #1 who has a better idea of what she wants. You just have to ask yourself what you want and who fits that criteria. Who has the qualities you want. If you want to see them for a short time you would have a better idea of who better fits your criteria.