Re: stopping pumping but got mastitis
My understanding is that what you should do in a situation like this is to cure the mastitis first, and only then try to reduce supply. So, pump as much as possible until the mastitis is under control, and then taper off by pumping less and less (less milk, less duration) each session. It sounds like you're not a great candidate for cold turkey weaning, so don't try that even after the mastitis is gone!
Now would probably also be a good time to add a soy lecithin supplement to your diet, and to reduce the amount of saturated fat that you're eating. Both of those things may help prevent/treat mastitis.
Good for you for EPing for 5 months! That's a hard commitment to hold to even when everything goes perfectly. If you're interested in continuing to some extent, you might want to check out this link: Partial Weaning & Combination Feeding. Lots of moms choose that path when they can't maintain a full supply anymore, or when exclusive breastfeeding just isn't working for them. It has a lot of the benefits of breastfeeding, plus the flexibility of using formula when necessary.
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