I've long felt that your love should make you want to be a better person.
I thought that was a great line in the 90's movie "Something's Gotta Give" that nailed the sentiment.
I'm hopelessly sentimental for liking that line I suppose.
But today I realized that parenthood makes that true in perhaps it's purest form. The birth of a child today really made me feel that I wanted to be a better person - or at least the best person I can be for that new person in the world.