This could be a bit of a cliché, but everytime I hear the phrase: Breastmilk is best for baby for the first six months. That is everytime I pick up her tin of formula.
I could only breastfeed for three months and then I gave up! So I feel guilty that I did not have more patience or willpower to keep breastfeeding and gave her the best possible start to life. DD was not gaining enough weight and was constantly hungry. My milk was getting less and less - don't know, but think it was stressing about her crying the whole night and not gaining the weight.
Don't get me wrong - I know that dd is well cared for and I know that it was the best move for us. But with all the breast is best campaining going around, there is that stubble regret and guilt.