Breastfeeding is very controversial and some women feel very badly (and guilty) when they can't do it, or they choose not to.
It is a personal decision. Very personal. Everyone has their different views and we can only make decisions for our own selves.
You do whatever you think is best for you. If you are not a healthy person, then formula feed. Breastfeeding doesn't come easy for everyone and it isn't always the 'best' option - any doctor will tell you that.
If you suffer from ppd, have to take medication, or your milk doesn't flow as it should - do not feel guilty for that. Your baby will do just fine whether it is breastfed or bottle fed.
Good luck!