How do I care for ivy?
Ivy needs moisture to thrive, but pine trees don't. So unfortunately, it's not a good planting combination. If you give the ivy all the moisture it needs, the pine tree may end up getting too much. I would recommend transplanting the ivy to another shady location that is moister, or that is under a deciduous tree that can handle more watering than pines.
As far as what is eating the leaves, that is an insect called the "lilac root weevil." The adult weevils feed on the edges of leaves, making those half-circle notches. But the lavae (the young weevils) are doing the most damage. They feed on the roots.
If you decide to leave your ivy where it is, use Bayer Tree and Shrub 12-month Treatment (not sure of exact name, but it contains that systemic insecticide called imidacloprid). This will kill the larvae as they feed on the plant.
Thanks for sending the pictures; they really helped me know what is going on.