Love is just Nature/God's way to make sure that people reproduce with one another or in the case of children, it's a way to protect your progeny.  It's completely artificial and fake.

For those who say they 'love' God, I say do you really , 'love' God or do you 'love' the idea that an all powerful deity will provide you with paradise and spare you from Hell.

Human's are selfish both from a biological and spiritual perspective.  Love isn't real.   

I really want to reply here, but I am not sure what to say...but here goes!

Love is undefinable, as you say, and doesn't have much to do with certain major details of living like paying bills.  But it kind of does too.  Why would you commit to solving major problems, like paying for things, if you didn't love the person you were doing this for?  Both partners, when they love each other, show it by doing things for one another and asking each others opinions about household matters and thinking of the other person when shopping or arranging furniture.  It all sounds so silly, but these are the actions of love.