Holly in Distress
We viewed your photos but we cannot say for sure what is going on. Some possibilities include a rot rot, canker disease, vole damage (a type of mouse that feeds on the roots of trees/shrubs - look around the base of the plants for silver dollar sized holes)
scale insects (are sucking sucking insects - look along the stems and underneath the foliage for round bumps) http://extension.umd.edu/hgic/plants/soft-scales-trees-and-shrubs, etc.
Has anything changed around the root system, drainage, change in grade, etc.
Hollies can be prone to root rots if the soil is poorly drained and cankers (dead areas on trunk/stems) http://extension.umd.edu/hgic/cankers-trees-and-shrubs
due to poor maintenance, stressed plants due to drought, etc.
It looks like the plant is stressed but is trying to put out new growth. All you can do is look for the above issues. Monitor the shrub and water during dry periods up until the ground freezes. Make sure mulch is no thicker than several inches and keep away from the base of the stem. Prune back next March, remove dead wood, and see if it grows back. If not, you will have to consider replacement.