Here's my opinion!
By the time they are 6 months, foals on pasture are taking very little milk from their dams. We wean at 6 months too and always go 'cold turkey'. Foals stay in their familiar field and the mares get moved right away - out of sight and hopefully out of hearing (although I know this is often not possible!) Never had trouble with either mares or foals, the mares seem only too pleased to be rid of their pesky, lively, often annoying babies! Most of the mares will get a full bag (never tight) for a couple of days, but dry up quickly thereafter. A mare 'in sight/near' her foal will continue to make milk/try to provide for it.
We always make sure we have at least two mares and foals as a minimum each year - foals need a young playmate to share their early life with, to race, chase and play with. If we do get landed with only one mare and foal in a season, then we borrow or take in another from a friend to avoid a single foal growing up without a companion - often offering a covering to one of our boys in return. At weaning our foal then has a buddy and our mare can go back with our herd/her friends and the borrowed mare can either go home or join our herd for the winter.
IMO you need to move your mare away from your foal, do not milk her, keep her away from lush pasture, suppliment with hay if necessary but no food/grain, until she dries up. Do you have a friend who would take her for a couple of weeks? Your mare needs company as much as your weaned foal does.
Good luck!
Anna