The bad stuff is just a consequence of loving someone in a very deep way.

I don't think I can define the "value of love" beyond saying that the upside is fairly basic stuff - fulfillment, joy, affection, pride, self-discovery, character building from not putting yourself first and from serving others, etc.

This deep connection is the good stuff. The really bad stuff is learning to let go of your kids, watching this connection change and hoping that it changes into something even deeper.