Okay, i'm soon going to be in this situation. The girl i've been with for two years has hurt me enough over the past two months. I'm going to tell you exactly how you're going to feel if you think about this more and more: EMOTIONAL ROLLER COASTER.
Yes, i used that term with my "girlfriend" when i was utterly pissed at her.
Yes, for me I have other girls who like me, but they would never be able to connect in the same intellectual level as i did with my girl right now.
If you crawl back to the ex, you're going to feel much more satisfied rather than being jealous.
but question is, can you? If you can, go for it.
If you can't, forget about her. You never will, it will always be somewhat of a roller coaster emotionally, but you can come close.