Bacon wrote:
So I'm a wee bit in love with my ex girlfriend again. What do.
Well there's two things you need to remember. The first thing is that, if these feelings are getting in the way of your feelings for your current girlfriend, you shouldn't keep it from her. There are few things worse than having things like these brought up long after there is any hope of talking about it while it is first becoming an issue and not being able to do anything about it. If it's just a little thing that's bothering you, then you can bring it up at your own discretion, obviously. Just don't leave anyone who is important to you in the dark.
The second thing to do is evaluate why the relationship didn't work in the first place, and see if that effects these feelings at all. If it was a mutual break up, then you should question the source of these resurrected feelings. If it was more on her end, then it really is perfectly natural for you to have feelings for her than never entirely went away. I see it happen to guys all the time. If it was of your own personal volition that the relationship didn't work, then you may be suffering from some confusion about the whole mess, and you'll need to sort it out yourself. 
Obviously it's sorta hard for me to lend advice considering I don't know the story with you and your ex. Obviously that's personal stuff, but if you wanted to talk to me about it or anything, you could PM me. Always here to help however I can.
edit: wait shit I apologize if you're not actually in a relationship anymore. I thought I had seen you mention that you were but I now realize I am not sure. Sorry for the assumption bro