Angels were created to serve God, but at the same time given free will and reason.  The result of this was that angels were capable of choosing sin as some did.

As for humans, free will gives them value to service rendered to God.  “In freely choosing to serve as the agents of divine purpose, angels are the living expression of the prayer, “Thy will be done.” ……David Connelly

Angels are presumed to be far superiour intellectually to humans, due to their physical swifness.

“Superior to human beingsd who have minds conjoined with bodies, the angels – minds without bodies – know without any dependence on sense-experience or imagination and have wills with freedom of choice but without being subject to the influence of bodily passions”. ……Mortimer Adler

Therefore, because anges don’t have bodies, their emotions lack the “feelings” of humans, but nevertheless, they are endowed with love.