A ninety-year-old man is sitting on a park bench, sobbing, when a young man walks by and asks him what's wrong. Through his tears the old man answers, "I'm in love with a twenty-five-year-old woman."
"What's wrong with that?" asks the young man.
Between the sobs and sniffles, he answers, "You can't understand. Every morning before she goes to work, we make love... At lunchtime she comes home and we make love again, and then she makes my favorite meal. In the afternoon when she gets a break, she rushes home and we have more sex, the best an old man could want. And then at supper time, and all night long, we make love." He breaks down, no longer able to speak.
The young man puts his arm around him. "I don't understand. It sounds like you have a perfect relationship. Why are you crying?"
The old man answers, again through his tears, "I forgot where I live."