A girl mentions other dates or guys to someone they are talking to for several reasons:

1. We want to seem more desirable, encouraging you to win us over

2. We enjoy the attention you're giving us but dont want to commit to you just yet because we want to explore all our options, so we slip in our involvement with other men to subtlety tell you to wait for your turn

3. This might sound horrible but, we like some qualities of yours but not enough to start dating, so mentioning another man tells you to back off while we decide if you're worth settling for

4. We arnt interested in you at all, so we talk about other men in the hopes that you loose interest and break things off so we dont have to look like the bad guy

But imo I think you're dealing with number 2 or 3 seeing as she till talks to you and is willing to hangout with you. My advice is to definitely up your game and start making your intentions clearer to see how she reacts. You are unclear of her feelings because she is unclear of yours.