I can sympathize with the process feeling slow and frustrating. It might not necessarily be low self esteem, though. You mention eating when you are stressed - there are many reasons that could be happening and not all of them come from low self esteem!
There are lots of ways to approach becoming less stressed...you can approach the issue from an emotional & mental standpoint, which is the perspective of this article here: www.sparkpeople.com/resource/wellness_arti
You can also sometimes find organizational ways around stress...by that, I mean figure out what is stressing you out and try to make it less stressful. For example, if you need more time to yourself, maybe you know another mom who is willing to trade off afternoons watching the kids; or maybe you know a young person who needs work that you would trust to babysit your kids for a while.