If it is laminitis then the most important thing--2 things really--are:
-proper hoof trimming--after two months of lameness there will likely be some changes in her hoofs. Probably there will be a tendency for the heels to grow fast & curl under, and her toes will probably have some separation, so that there will be some dishing in the front of the hoof. The heels must be kept trimmed down, and the toes must be cut back to get rid of the separated portion. I don't mean to cut the toes very short, but to trim them back--dub them so to speak--to make the breakover easy. If the feet get long the separated portion of the toe will make breakover difficult--and the stress on the long toe will make the separation worse, which in turn will cause more soreness. She may need to be touched up every 3-4 weeks. The idea is to maintain the hoof in as normal a shape as possible--allowing the feet to be too long and become dished is very bad.
-diet--I would feed this mare only grass hay with a bit of grain. I know some people won't give grain to a horse that has had laminitis, but I have some previously foundered horses here & have never had a problem with giving them grain (plain rolled oats usually, though in the case of a bred mare I do also give 14% pellets). I'm guessing that in this mare's case pasture was the culprit in foundering her--even if the grass is gone now she probably had more grass a couple months back when she first got lame? That being the case I would take her off pasture completely & give her only grass hay until she is no longer lame.
My previously foundered mares are out on pasture this summer, but the pasture they are on is pretty much chewed right down. We had so much rain this summer that my corrals are much too muddy, and so I turned these girls out on pasture where they can be out of the mud. They do get a little bit of grazing and are on hay--mostly grass hay with a bit of alfalfa mixed in. None of them were lame when I put them out and all are staying sound even with the bit of green grass and alfalfa that they are getting--and they move around lots so the exercise is good for them. Had one of them been lame I'd have had to keep her in and move her to a drier paddock--there's no way I'd give any green grass or alfalfa to a horse that was at all lame with laminitis....my point being that with the mare you ask about, I'd keep her on dry feed until she's over this bout of lameness. She would get pasture only when it's very poor, and only if she were sound, and then I'd watch her like a hawk for for any sign of recurring soreness. Some horses cannot handle anything but dry grass hay once they founder, and others can do quite well even on a richer diet as long as their feet are kept properly trimmed and are monitored closely.
Banamine doesn't usually have a lot of benefit for laminitis, unfortunately. Bute is the drug of choice for that kind of lameness, but of course bute isn't recommended for either minis or pregnant mares.
I would keep this mare somewhere with soft footing--a deep bedded shed and a corral with soft footing, no stones would be my ideal. You can tape styrofoam to the bottoms of her feet to cushion her while she's very lame.