I know one or two who have done it but it seems taxing. I am unsure about feeding through pg again because it left me feeling very depleted last time.

I would get bloods done to check for deficiencies and target those with vitamins. I would also look for extra support to get more rest. You will need to get lots of calories too, so possibly look at seeing a naturopath/dietician.

I am all for long term breastfeeding and tandem feeding, but I think you need to make sure there's enough left for you, because your needs will be last on the list.