I find my eyes going only to what my child can't do.

Noticing what they can't do comes precisely from caring, and it's natural. A tip: parenting easily becomes "wanting what isn't there." Deliberately doing a "you-did-it search"—for small can-dos, changes from before, and the child's own good points—and putting them into words creates a good cycle for the child's confidence and for the parent's own feelings. Making it a system—jotting one down a day, keeping photos—helps it continue. You, who can find "can't," can surely find "did it" too.