Don't listen to those "nay-sayers." I think you've set a very realistic goal for yourself.
You don't say exactly what you're addicted to but you do mention you're breastfeeding. Are you tired? I know that sometimes that's one of my triggers to mindlessly eat.
Do you like to cook? If so, adding beans to your daily diet really ups not only your fiber intake but that feeling of fullness we're sometimes looking for (although you may want to start small to be sure they don't have any ill effects on your baby).
And just like Psalmandpraise mentions, eat those veggies. (hummus is also a good dipping choice)
Summer is a great time to try new veggies - if you have a local farmers market I've learned the people there are always willing to talk about ways to prepare something you may never have tried before (spaghetti squash?, rhubarb?)
And use the Sparkpeople food tracker (and all the other resources here). They can literally change your life!