<human>: Can you provide a brief overview of the text?

Almost two months ago I met this girl A (23) and we really hit it off. However, I found out fairly quickly that she had just gotten out of a four year relationship, which was also her first and only. This means that dating in general is a big deal for her. Because of this I figured it was better to back off, but because we really liked each other we have kept in touch ever since. Now last weekend, I decided to ask her out. She said yes, but was very nervous about it, so I suggested that we waited until she actually felt ready, which she was pleased with. Since then she has been hinting more and more at her and me becoming a thing, in different ways, such as "Oh we should do this and this.." or "I really wanna show you around my home town.". Therefore, I have been getting my hopes up about it.

However, when I first met her I decided that I was not gonna put all my eggs in her basket, as I figured (and still do) that it is possible that she may never comes around.

Because of this I have been dating this other girl S (22). S is a really amazing girl, sweet, fun, and attractive, and we have really had a great time together. I like her a lot. But there is something wrong. There is a spark, but the other girl (A) is too stuck in my mind. When I was with S today there was actually times where I was thinking about how I should dump her, and I was picking out things wrong with her in my head. I really hate myself for doing it, but I struggle not to.

What bothers me is that I am about to ruin this great relationship with S over the possibility of a relationship with A, which might not even be that great! Should I forget about A? Dump S? Or is there a happy medium where I close neither door?
<bot>: Can't get one girl (23) out of my head, and it is ruining my ability to make relations with other girls. I can't just forget about her as she is still a possible relationship.