I am writing this right after reading your post, and not reading any of the replies, as to not be influenced with anyone's opinion. So if I repeat anything that's been said already, I apologize.
That is a very good idea, Krista, to build up the relationship from the bottom, up. It is very possible to build up that relationship over again. However, it will take lots of hard work from the both of you. It might be very hard to go from being "together" to being friends, and then back to being "together" again. It will be very awkward. I hope it's not doomed for a disappointment.
Also, I hope you're not getting your hopes up, saying this will definitely work. You're putting yourself at the risk of being hurt. If it doesn't work, you might just have to accept that relationships don't always work out, and you might just have to move on.
Best of luck with the situation, I hope things work out in your favor.
You think yourself a failure, but perhaps the biggest loss is winning...