love is...

... enduring, kind, selfless, bearing, believing, hopeful,
devoid of evil, envy and arrogance, and is delighted in truth.
(The Bible: 1 Corinthians 13:4-7)

Deep feelings in a positive direction can ride easily with equally deep feelings of the opposite nature that are much like envy, selfishness, arrogance and unkindness. Love, after all, cannot sing sweet all the time, right? But I have come to realize and accept that love is not a feeling.

Love
is a verb

It is a doing-word that involves quite a bit of doing and giving. It is not easy to endure, be consistently kind or selfless. It is very difficult to not succumb to boasting or feelings of envy. It is hard work to do something unconditionally... but that is exactly what love requires, and the depth of our love is measured by what we are willing to give and not by what we feel.

Love
is sacrifice

and God
is the greatest example.
'In this was manifested the love of God toward us, because that God sent his only begotten Son into the world that we might live through him.'
- The Bible: 1 John 4:9