I think you are in a bad place and its unfortunate that you live in a small town where its easy to run into her. Considering that you've been apart for so long now, she's consistently been with this other guy and she's given you really nothing to indicated she wants to get back together, you are just going to have to accept your break up and move on. I realize that's way easier said than done, but holding out hope that she will come back is unfair to yourself and truthfully probably not in your best interest (if she did come back).

When you go to these bars, are you going by yourself? If you are, are you maybe going on purpose to "accidentally" bump into her? Perhaps you need to take a break from the bar scene in your area for a while.

I know it has to be extremely hard to get over such a long relationship, but you have to start working on moving forward or you will be left in a mess and everything around you will keep moving forward without you.

Good luck to you. And I'm really sorry you are going through all this.