I don't have anything insightful to say other than I think it is healthy to do what you can when you can, try to live by your ideals as much as possible, but not to beat yourself up if you don't do things perfectly. Think about how your children will feel when they are grown. Will they be happy that you tried to be perfect and imposed perfection on them, or will they be happy that they had a mom who was able to relax some of her ideals at times? Not saying that you are trying to impose perfection on your kids, mind you; it sounds like you want to do the best you can and teach your children the importance of your beliefs.
I'm not sure if I'm even touching the point of your post as it sounds like you are more concerned about changing yourself and the difficulty therein. I see it that I came from a background much different than the one I'm trying to raise my daughter in, so already I've changed some and my daughter will benefit by that. I hope she will be even more likely to embrace my ideals and carry them farther than I can. Or she may strike out on a completely different path, who knows, but I like to think that the changes in myself will be magnified 10 fold in my offspring and that each generational change will reap benefits.