Thinking of expanding

I am considering adding addtional stories to my list, but my worry is getting caught up in another story line without finishing the one I have already began. I have done this in the past, where I think I can handle writing more than one story at a time, but then forget the first while I get caught up with the new plot.

Currently, I am not only working on my "Girls' and Boys" on Mibba, but also on another story (independent of any writing sites, just on my own) but I have hit a small wall that I am afraid to tackle, so I'm avoiding it. That is why I started my mibba site and the story "Girls and Boys," in order to hopefully get inspiration from writing something else, and be able to tackle this other hurdle.

So, the question remains, would adding another story be too much? Would it be best to simply focus on one story at a time, or would it be best to try writing another plot in order to evoke the needed inspiration for this other book that I am writing?