Parents beat their kids supposedly out of love. Love is not a guiding force or a source of strength. My daughter is 13 and has various (not serious but still challenging) conditions which need to be overcome and it's very tiring. I get my strength from my hope for her future. It is what keeps me going. My hope, and I guess my fear that if I don't, her future will not be a good one.
I absolutely love her with every fiber of my being, but if love was all you needed to give you strength, there wouldn't be so many divorces.