Sometimes we find ourselves through the act of giving, you mentioned a lack of freedom several times.
I have two kids and married a man with 3, it was crazy, messy and brilliant. Those kids are now young adults, several of them with children of their own.
There were good times and bad, but I guess some of my best and worst moments in life are directly related to those kids.
Nobody can describe it, along with those moments of giving and frustration is an overpowering love, protection and pride.
True, it is hard to describe. Even in people who have let their children down I see this love and pride, and it triples their guilt. It is a hard thing to describe because it is so fundamental.