Poets do their best, they really do; but it's impossible to define. There are of course a myriad kinds: that for your child, that for a good and reliable friend, that for an elderly relative. Even that for a place and that for a cool idea. And then there is that love. That love where the heart soars, where the heart beats faster, where a 'sweet nothing' whispered changes human biochemistry, where a word in a text encapsulates a feeling which combusts a passion.This is 'that love': so strong that it does and will go on for ever despite a universe which throws everything it can to disrupt, to test and to jolt off course.
That is a love to know, to cherish, to hold, to value, to believe in, to know will never die. Whatever.