I'm no expert but my Ivy want to be watered and allowed to dry out before watering again. If the roots get too wet they literally drowned. Try letting the soil dry out and cut back all the foliage that looks wilted. After a few days of dry soil give a quick drink and do not let the soil stand in water. It may come back slowly. Also check for insects hiding under the foliage. Also this foliage prefers good light but no direct sun so next to a window would be better than lightening. Good luck.
